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122-452: Lenovo lines (former/ current ): The ThinkPad X series is a line of notebook computers and convertible tablets produced by Lenovo as part of the ThinkPad family. The ThinkPad X series is traditionally the range best designed for mobile use, with ultraportable sizes and less power compared to the flagship ThinkPad T series . It was initially produced by IBM until 2005. IBM announced

244-484: A 5% share. Lenovo and NEC also agreed to explore cooperating in other areas such as servers and tablet computers. Roderick Lappin, chairman of the Lenovo–NEC joint venture, told the press that the two companies will expand their co-operation to include the development of tablet computers. In June 2011, Lenovo announced that it planned to acquire control of Medion , a German electronics manufacturing company. Lenovo said

366-461: A BGA heat sink directly to the component. The clips make use of the gap created by the ball grid array (BGA) between the component underside and PCB top surface. The clips therefore require no holes in the PCB. They also allow for easy rework of components. For larger heat sinks and higher preloads, push pins with compression springs are very effective. The push pins, typically made of brass or plastic, have

488-524: A battery life of two hours. Battery configuration Processor Weight Screen resolution Graphics Laptop storage combinations (excluding WWAN slot) Laptop memory The X Series laptops released by Lenovo in 2007 were the X61 , the X61s , and the X61 tablet . The X61 received mixed user reviews on CNET , with some users reporting display problems and delivery delays, while others praised

610-569: A change in typography or the look of the logo. We asked 'If we really are a net-driven, customer-centric company, what should the logo look like?' We came up with the idea of a digital logo first [...] designed to be used on the internet and adaptable to context." In early June 2015, Lenovo announced plans to sell up to US$ 650 million in five-year bonds denominated in Chinese yuan. The bonds were sold in Hong Kong with coupon ranging from 4.95% to 5.05%. This

732-477: A closer relationship with Intel, the maker of most server processors, through its acquisition of IBM's x86-based server business. On 1 October 2014, Lenovo closed its acquisition of IBM's server division, with the final price put at $ 2.1 billion. Lenovo said this acquisition came in at a price lower than the previously announced $ 2.3 billion partially because of a change in the value of IBM inventories. The deal has been already approved by Europe and China. Per Forbes,

854-534: A company doing quality checks on computers. It also tried and failed to market a digital watch. In May 1988, Lenovo placed its first recruitment advertisement on the front page of the China Youth News . Such ads were quite rare in China at the time. Out of the 500 respondents, 280 were selected to take a written employment exam. 120 of these candidates were interviewed in person. Although interviewers initially only had

976-461: A dozen different CPUs and three screen options; the top of the range was a WXGA+ LED-Backlit TN Panel. The X200s features cooler components (made possible with the fan design modeled on owl-wings). However, both laptops did not have a touchpad (only the TrackPoint), no HDMI , DVI , or DisplayPort , and no built-in optical drive. The X200 series included tablet PC models, designated by the usage of

1098-730: A durable design." The X-series laptop styles include traditional ultraportables, as well as convertible tablet designs. According to Lenovo, the ThinkPad X-series laptops include low power processors, offer long battery life, and several durability features such as a Roll Cage (Magnesium Frame around the Display), magnesium alloy covers, and a spill-resistant keyboard but currently lacks a replaceable battery and upgradable RAM slots. Battery configuration Processor Weight Screen resolution Graphics Laptop storage combinations (excluding WWAN slot) Laptop memory The X20

1220-457: A fan, but in all instances, eventually to the environment. Two additional design factors also influence the thermal/mechanical performance of the thermal design: As power dissipation of components increases and component package size decreases, thermal engineers must innovate to ensure components won't overheat . Devices that run cooler last longer. A heat sink design must fulfill both its thermal as well as its mechanical requirements. Concerning

1342-490: A final sale in 2011 completing their divestment. Mary Ma , Lenovo's chief financial officer from 1990 to 2007, was in charge of investor relations. Under her leadership, Lenovo successfully integrated Western-style accountability into its corporate culture. Lenovo's emphasis on transparency earned it a reputation for the best corporate governance among mainland Chinese firms. While Hong Kong-listed firms were only required to issue financial reports twice per year, Lenovo followed

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1464-411: A flexible barb at the end that engages with a hole in the PCB; once installed, the barb retains the pin. The compression spring holds the assembly together and maintains contact between the heat sink and component. Care is needed in selection of push pin size. Too great an insertion force can result in the die cracking and consequent component failure. For very large heat sinks, there is no substitute for

1586-675: A governmental research institute. Then known as Legend, the company developed numerous electronics before focusing on personal computers. Co-founder Liu Chuanzhi incorporated Legend in Hong Kong in an attempt to raise capital and was successfully permitted to build computers in China. It listed on the Hong Kong Stock Exchange in 1994 and became the largest PC manufacturer in China and eventually in Asia; they were also domestic distributors for HP printers, Toshiba laptops, and others. After

1708-546: A half-gallon of milk", despite the presence of a 12.1-inch Thin-film transistor (TFT LCD) display. These design values—thin and light—continued to be integral to the ThinkPad X-series laptops' design and marketing, even after the purchase of IBM's Personal Computing Division by Lenovo . The first X Series ThinkPad released by Lenovo was the X41 in 2005. The ThinkPad X-series laptops from Lenovo were described by Trusted Reviews as "combining an ultraportable's weight and form factor with

1830-439: A heat sink, this means that heat does not distribute uniformly through the heat-sink base. The spreading resistance phenomenon is shown by how the heat travels from the heat source location and causes a large temperature gradient between the heat source and the edges of the heat sink. This means that some fins are at a lower temperature than if the heat source were uniform across the base of the heat sink. This nonuniformity increases

1952-696: A joint venture with Fujitsu and the Development Bank of Japan (DBJ). In the joint venture, Fujitsu would sell Lenovo a 51% stake in Fujitsu Client Computing Limited . DBJ would acquire a 5% stake. In September 2018, Lenovo and NetApp announced about strategic partnership and joint venture in China. As part of strategic partnership Lenovo started two new lines of storage systems: DM-Series and DE-Series. Both storage systems using Lenovo hardware and NetApp software: DM-Series using ONTAP OS and DE-Series SANtricity OS. In 2018, Lenovo became

2074-577: A new "Thin and Light" sub-line. Specifications: Three years after the release of the X30, upon acquiring the ThinkPad division, Lenovo released the ThinkPad X41 ultraportable laptop and the ThinkPad X41 tablet. The X41 tablet was convertible, with the capacity to function as a tablet PC and an ultraportable laptop. The X32 was introduced in 2005. The numbering system was irregular, as it was actually introduced after

2196-463: A new 9-cell battery for extended running time up to 9.8 hours, weight as low as 1.34 kg (2.95 lb), and an Intel Core 2 Duo CPU up to 2.66   GHz. Lenovo released X200s on 23 September 2008. It differed from the standard X200 in being lighter, having longer battery life, and running more quietly due to an "owl fan" design for cooling taken from the X300. The X200s was available with more than half

2318-542: A new logo at Lenovo Tech World in Beijing, with the slogan "Innovation Never Stands Still" ( Chinese : 创新无止境 ). Lenovo's new logo, created by Saatchi, can be changed by its advertising agencies and sales partners, within restrictions, to fit the context. It has a lounging "e" and is surrounded by a box that can be changed to use a relevant scene, solid color, or photograph. Lenovo's Chief Marketing Officer David Roman said, "When we first started looking at it, it wasn't about just

2440-407: A rectangular copper body. Fin efficiency is one of the parameters that makes a higher-thermal-conductivity material important. A fin of a heat sink may be considered to be a flat plate with heat flowing in one end and being dissipated into the surrounding fluid as it travels to the other. As heat flows through the fin, the combination of the thermal resistance of the heat sink impeding the flow and

2562-454: A satellite in space, a 100 °C (373 K) surface facing the Sun will absorb a lot of radiant heat, because the Sun 's surface temperature is nearly 6000 K, whereas the same surface facing deep space will radiate a lot of heat, since deep space has an effective temperature of only several Kelvin. Heat dissipation is an unavoidable by-product of electronic devices and circuits. In general,

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2684-462: A smaller heatsink and a slightly thinner case with a different battery form factor, although it could use standard X60 batteries with a plastic adapter. In its review of the ThinkPad X60/X60s, Notebook Review called the laptop, "Hands down the best performing ultraportable on the market", while raising issues about the design and the lack of an optical drive. The two laptops were available in

2806-435: A team of engineers led by Liu Chuanzhi and Danny Lui . Initially specializing in televisions , the company migrated towards manufacturing and marketing computers. Liu Chuanzhi and his group of ten experienced engineers , teaming up with Danny Lui , officially founded Lenovo in Beijing on November 1, 1984, with 200,000 yuan . The Chinese government approved Lenovo's incorporation on the same day. Jia Xufu (贾续福), one of

2928-448: A thermal resistance (heat sink to ambient air) ranging from 0.4 °C/W for a large sink meant for TO-3 devices, up to as high as 85 °C/W for a clip-on heat sink for a TO-92 small plastic case. The popular 2N3055 power transistor in a TO-3 case has an internal thermal resistance from junction to case of 1.52 °C/W . The contact between the device case and heat sink may have a thermal resistance between 0.5 and 1.7 °C/W , depending on

3050-488: A variety of configurations. Later X60 models used 64-bit Core 2 Duo CPUs, and some X60s were available with a lightweight LCD panel. Typical specifications of the laptops are provided below: The ThinkPad X60 Tablet was praised by reviewers. LAPTOP Magazine said the ThinkPad X60 Tablet "raises the bar for business-class convertibles". The most significant issue raised was the low capacity 4-cell battery, which provided

3172-421: A variety of heat-generating bodies to a heat sink. Placing a conductive thick plate as a heat-transfer interface between a heat source and a cold flowing fluid (or any other heat sink) may improve the cooling performance. In such arrangement, the heat source is cooled under the thick plate instead of being cooled in direct contact with the cooling fluid. It is shown that the thick plate can significantly improve

3294-653: Is a Chinese-American multinational technology company specializing in designing, manufacturing, and marketing consumer electronics , personal computers , software, servers, converged and hyperconverged infrastructure solutions, and related services. Its global headquarters are in Beijing , and Morrisville, North Carolina , United States; it has research centers at these locations, elsewhere in China, in Stuttgart, Germany , and in Yamato, Japan . Lenovo originated as an offshot of

3416-540: Is a manufacturer of personal computers, smartphones, televisions, and wearable devices. Some of the company's earliest products included the KT8920 mainframe computer and a circuit board that allowed IBM-compatible personal computers to process Chinese characters. One of its first computers was the Tianxi ( 天禧 ), released in 1998 in the Chinese market. It became the best selling computer in Chinese history in 2000. Lenovo markets

3538-445: Is for rough surfaces, the major contribution to the resistance is made by the gaps. To decrease the thermal contact resistance, the surface roughness can be decreased while the interface pressure is increased. However, these improving methods are not always practical or possible for electronic equipment. Thermal interface materials (TIM) are a common way to overcome these limitations. Properly applied thermal interface materials displace

3660-517: Is frequently air, but can also be water, refrigerants or oil. If the fluid medium is water, the heat sink is frequently called a cold plate. In thermodynamics a heat sink is a heat reservoir that can absorb an arbitrary amount of heat without significantly changing temperature. Practical heat sinks for electronic devices must have a temperature higher than the surroundings to transfer heat by convection, radiation, and conduction. The power supplies of electronics are not absolutely efficient, so extra heat

3782-426: Is increased by decreasing the fin aspect ratio (making them thicker or shorter), or by using a more conductive material (copper instead of aluminium, for example). Another parameter that concerns the thermal conductivity of the heat-sink material is spreading resistance. Spreading resistance occurs when thermal energy is transferred from a small area to a larger area in a substance with finite thermal conductivity. In

ThinkPad X series - Misplaced Pages Continue

3904-453: Is low, such as a flat non-finned panel with low airflow, radiative cooling can be a significant factor. Here the surface properties may be an important design factor. Matte-black surfaces radiate much more efficiently than shiny bare metal. A shiny metal surface has low emissivity. The emissivity of a material is tremendously frequency-dependent and is related to absorptivity (of which shiny metal surfaces have very little). For most materials,

4026-536: Is mechanically soft. Aluminium alloys 6060 (low-stress), 6061 , and 6063 are commonly used, with thermal conductivity values of 166 and 201 W/(m·K) respectively. The values depend on the temper of the alloy. One-piece aluminium heat sinks can be made by extrusion , casting , skiving or milling . Copper has excellent heat-sink properties in terms of its thermal conductivity, corrosion resistance, biofouling resistance, and antimicrobial resistance (see also Copper in heat exchangers ). Copper has around twice

4148-535: Is more expensive than tape, but provides a greater mechanical bond between the heat sink and component, as well as improved thermal conductivity. The epoxy chosen must be formulated for this purpose. Most epoxies are two-part liquid formulations that must be thoroughly mixed before being applied to the heat sink, and before the heat sink is placed on the component. The epoxy is then cured for a specified time, which can vary from 2 hours to 48 hours. Faster cure time can be achieved at higher temperatures. The surfaces to which

4270-502: Is not expected to significantly affect earnings. More specifically, Stoneware was acquired to further Lenovo's efforts to improve and expand its cloud-computing services. For the two years prior to its acquisition, Stoneware partnered with Lenovo to sell its software. During this period Stoneware's sales doubled. Stoneware was founded in 2000. As of September 2012, Stoneware is based in Carmel, Indiana, and has 67 employees. Lenovo re-entered

4392-430: Is one of the most cost-effective heat sink attachment materials. It is suitable for low-mass heat sinks and for components with low power dissipation. It consists of a thermally conductive carrier material with a pressure-sensitive adhesive on each side. This tape is applied to the base of the heat sink, which is then attached to the component. Following are factors that influence the performance of thermal tape: Epoxy

4514-494: Is only the second sale of bonds in Lenovo's history. Financial commentators noted that Lenovo was paying a premium to list the bonds in yuan given relatively low costs for borrowing in US dollars. Lenovo said that its x86 servers will be available to all its channel partners. Lenovo plans to cut prices on x86 products in order to gain market share. This goes in alliance with IBM 's vision of

4636-437: Is produced that may be detrimental to the function of the device. As such, a heat sink is included in the design to disperse heat. Fourier's law of heat conduction shows that when there is a temperature gradient in a body, heat will be transferred from the higher-temperature region to the lower-temperature region. The rate at which heat is transferred by conduction, q k {\displaystyle q_{k}} ,

4758-459: Is proportional to the product of the temperature gradient and the cross-sectional area through which heat is transferred. When it is simplified to a one-dimensional form in the x direction, it can be expressed as: For a heat sink in a duct, where air flows through the duct, the heat-sink base will usually be hotter than the air flowing through the duct. Applying the conservation of energy, for steady-state conditions, and Newton's law of cooling to

4880-526: Is still very much in use. In general, a heat sink performance is a function of material thermal conductivity, dimensions, fin type, heat transfer coefficient , air flow rate, and duct size. To determine the thermal performance of a heat sink, a theoretical model can be made. Alternatively, the thermal performance can be measured experimentally. Due to the complex nature of the highly 3D flow in present applications, numerical methods or computational fluid dynamics (CFD) can also be used. This section will discuss

5002-548: Is the flared fin heat sink, where the fins are not parallel to one another. Flaring the fins decreases flow resistance and makes more air go through the heat-sink fin channel; otherwise, more air would bypass the fins. Slanting them keeps the overall dimensions the same, but offers longer fins. Examples of the three types are shown in the image on the right. Forghan, et al. have published data on tests conducted on pin fin, straight fin, and flared fin heat sinks. They found that for low air approach velocity, typically around 1 m/s,

ThinkPad X series - Misplaced Pages Continue

5124-409: Is the need for holes in the PCB. Thermal contact resistance occurs due to the voids created by surface roughness effects, defects and misalignment of the interface. The voids present in the interface are filled with air. Heat transfer is therefore due to conduction across the actual contact area and to conduction (or natural convection) and radiation across the gaps. If the contact area is small, as it

5246-418: Is to pack as much surface area into a given volume as possible, while working in any orientation of fluid flow. Kordyban has compared the performance of a pin-fin and a straight-fin heat sink of similar dimensions. Although the pin-fin has 194 cm surface area while the straight-fin has 58 cm , the temperature difference between the heat-sink base and the ambient air for the pin fin is 50 °C , but for

5368-572: The IdeaPad , Yoga , LOQ, and Legion consumer lines of notebooks, and the IdeaCentre , LOQ, Legion, and ThinkCentre lines of desktops. Lenovo is also part of a joint venture with NEC , named Lenovo NEC Holdings, that produces personal computers for the Japanese market. The company also operates Motorola Mobility which produced smartphones. Lenovo was founded in Beijing on 1 November 1984 as Legend by

5490-763: The Moto X , Moto G , Droid Turbo , and the future Motorola Mobility product roadmap, while Google retained the Advanced Technologies & Projects unit and all but 2,000 of the company's patents. Lenovo received royalty free licenses to all the patents retained by Google. Lenovo received approval from the European Union for its acquisition of Motorola in June 2014. The acquisition was completed on 30 October 2014. Motorola Mobility remained headquartered in Chicago, and continued to use

5612-505: The ThinkPad X series (initially the X20) in September 2000 with the intention of providing "workers on the move with a better experience in extra-thin and extra-light mobile computing." The ThinkPad X series replaced both the 240 and 570 series during IBM's transition from numbered to letter series during the early 2000s. The first X Series laptops were "slimmer than a deck of cards" and "lighter than

5734-408: The ThinkPad , IdeaPad , Yoga , Legion and Xiaoxin ( 小新 ; Chinese market only) lines of laptops, as well as the IdeaCentre and ThinkCentre lines of desktops. It expanded significantly in 2005 through its acquisition of IBM 's personal computer business, including its ThinkPad and ThinkCentre lines. As of January 2013, shipments of THINK-branded computers have doubled since Lenovo's takeover of

5856-442: The die temperature of the integrated circuit. Thermal adhesive or thermal paste improve the heat sink's performance by filling air gaps between the heat sink and the heat spreader on the device. A heat sink is usually made out of a material with a high thermal conductivity , such as aluminium or copper. A heat sink transfers thermal energy from a higher-temperature device to a lower-temperature fluid medium. The fluid medium

5978-534: The "t" suffix, primarily the X230t. Lenovo released X200 tablet on 9 September 2008. Like other tablet-designated models this added a convertible screen assembly containing a touch digitizer with pen and buttons on the screen front for operating the device without access to keyboard and buttons in converted mode. Lenovo Lenovo Group Limited , trading as Lenovo ( / l ə ˈ n oʊ v oʊ / lə- NOH -voh , Chinese : 联想 ; pinyin : Liánxiǎng ),

6100-633: The Hong Kong market in March 2000 and raised about US$ 212 million . It rebranded to the name Lenovo in 2003 and began making acquisitions to expand the company. Lenovo acquired IBM 's personal computer business in 2005, including the ThinkPad laptop and ThinkCentre desktop lines. Lenovo's acquisition of IBM's personal computer division accelerated access to foreign markets while improving Lenovo's branding and technology. Lenovo paid US$ 1.25 billion for IBM's computer business and assumed an additional US$ 500 million of IBM's debt. This acquisition made Lenovo

6222-532: The LePhone. At the same time, LeGarden counted 2,774 individual developers and 542 developer companies as members. On January 27, 2011, Lenovo formed a joint venture to produce personal computers with Japanese electronics firm NEC . The companies said in a statement that they would establish a new company called Lenovo NEC Holdings, to be registered in the Netherlands. NEC received US$ 175 million in Lenovo stock. Lenovo

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6344-547: The LenovoEMC brand, and designed products for small and medium-sized businesses that could not afford enterprise-class data storage. Lenovo has since retired all of the LenovoEMC products on their product page advising that the products are no longer available for purchase on lenovo.com. IBM sold its x86-based server lines, including System x and Blade Center , to Lenovo in 2014. Lenovo says it will gain access to more enterprise customers, improve its profit margins, and develop

6466-507: The Motorola brand, but Liu Jun, president of Lenovo's mobile device business, became the head of the company. In April 2014, Lenovo purchased a portfolio of patents from NEC related to mobile technology. These included over 3,800 patent families in countries around the world. The purchase included standards-essential patents for 3G and LTE cellular technologies and other patents related to smartphones and tablets. In May 2015, Lenovo revealed

6588-592: The No. 2 provider of smartphones in the domestic Chinese market in 2012. However, with approximately 100 smartphone brands sold in China, this only equated to a 10.4% market share. In May 2012, Lenovo announced an investment of US$ 793 million in the construction of a mobile phone manufacturing and R&D facility in Wuhan , Hubei . In 2013, Lenovo created a joint venture with EMC named Iomega . The venture took over Iomega's business and rebranded all of Iomega's products under

6710-587: The United States Department of Treasury Committee on Foreign Investment in the United States (CFIUS) was reportedly the last major hurdle for Lenovo, since the United States has the strictest policies. According to Timothy Prickett-Morgan from Enterprise Tech, the deal still awaits "approval of regulators in China, the European Commission , and Canada". After closing, Lenovo said that its goal

6832-668: The X22 but with faster processors (800 or 866   MHz), bigger hard drives up to 30   GB, Bluetooth, and the IBM Security Sub System on selected models. Same as the X23 with even faster processors: 1.06 to 1.13   GHz. Full-powered successor to the X2x line with a completely redesigned case. However, they shared much of the technology. 830MG chipset with Intel Extreme Graphics GPU. Maximum of 1   GiB RAM, thanks to two RAM slots. FireWire

6954-509: The X40, but using the older X3x chassis design. It was also more powerful than the X40 and X41 units, due to the use of faster full-voltage Dothan processors and standard 2.5-inch 5400/7200   RPM hard drives. It was a very short-lived model, discontinued within months of introduction. On this model, IBM included Gigabit LAN and the Security Sub System on all models. The X32 and X41 are two of

7076-455: The ability to build a new corporate culture. At the end of its first two years, Lenovo Group had met many of its original challenges, including integrating two disparate cultures in the newly formed company, maintaining the Think brand image for quality and innovation, and improving supply chain and manufacturing efficiencies. However, Lenovo had failed to meet a key objective of the merger: leveraging

7198-542: The acquisition would double its share of the German computer market, making it the third-largest vendor by sales (after Acer and Hewlett-Packard ). The deal, which closed in the third quarter of the same year, was claimed by The New York Times as "the first in which a Chinese company acquired a well-known German company." This acquisition will give Lenovo 14% of the German computer market. Gerd Brachmann, chairman of Medion, agreed to sell two-thirds of his 60 per cent stake in

7320-515: The acquisition, Lenovo announced that its subsequent acquisitions would be concentrated in software and services. In September 2012, Lenovo agreed to acquire the United States–based software company Stoneware, in its first software acquisition. The transaction was expected to close by the end of 2012; no financial details have been disclosed. Lenovo said that the company was acquired in order to gain access to new technology and that Stoneware

7442-431: The aforementioned methods for the determination of the heat sink thermal performance. One of the methods to determine the performance of a heat sink is to use heat transfer and fluid dynamics theory. One such method has been published by Jeggels, et al., though this work is limited to ducted flow. Ducted flow is where the air is forced to flow through a channel which fits tightly over the heat sink. This makes sure that all

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7564-399: The air goes through the channels formed by the fins of the heat sink. When the air flow is not ducted, a certain percentage of air flow will bypass the heat sink. Flow bypass was found to increase with increasing fin density and clearance, while remaining relatively insensitive to inlet duct velocity. The heat sink thermal resistance model consists of two resistances, namely the resistance in

7686-412: The air that is present in the gaps between the two objects with a material that has a much-higher thermal conductivity. Air has a thermal conductivity of 0.022 W/(m·K) while TIMs have conductivities of 0.3 W/(m·K) and higher. When selecting a TIM, care must be taken with the values supplied by the manufacturer. Most manufacturers give a value for the thermal conductivity of a material. However,

7808-554: The air, and radiation . Heat transfer by radiation is a function of both the heat-sink temperature and the temperature of the surroundings that the heat sink is optically coupled with. When both of these temperatures are on the order of 0 °C to 100 °C, the contribution of radiation compared to convection is generally small, and this factor is often neglected. In this case, finned heat sinks operating in either natural-convection or forced-flow will not be affected significantly by surface emissivity . In situations where convection

7930-827: The authority to hire 16 people, 58 were given offers. The new staff included 18 people with graduate degrees, 37 with undergraduate degrees, and three students with no university-level education. Yang Yuanqing , the current chairman and CEO of Lenovo, was among that group. Liu Chuanzhi received government permission to form a subsidiary in Hong Kong and to move there along with five other employees. Liu's father, already in Hong Kong along with Lui, furthered his son's ambitions through mentoring and facilitating loans. Liu moved to Hong Kong in 1988. To save money during this period, Liu and his co-workers walked instead of taking public transportation. To keep up appearances, they rented hotel rooms for meetings. In 1990, Lenovo started to manufacture and market computers using its own brand name. Some of

8052-665: The brand, with profit margins thought to be above 5%. Lenovo aggressively expanded the THINK brand away from traditional laptop computers in favor of tablets and hybrid devices such as the ThinkPad Tablet 2 , ThinkPad Yoga , ThinkPad 8 , ThinkPad Helix , and ThinkPad Twist ; the shift came as a response to the growing popularity of mobile devices, and the release of Windows 8 in October 2012. Lenovo achieved significant success with this high-value strategy and in 2013 controlled more than 40% of

8174-496: The case size and use of grease or insulating mica washer. The materials for heat sink applications should have high heat capacity and thermal conductivity in order to absorb more heat energy without shifting towards a very high temperature and transmit it to the environment for efficient cooling. The most common heat sink materials are aluminium alloys . Aluminium alloy 1050 has one of the higher thermal conductivity values at 229 W/(m·K) and heat capacity of 922 J/(kg·K), but

8296-679: The combined strength of the two companies to grow volume and market share. In order to achieve success, Lenovo embraced diversification at multiple levels- business model, culture, and talent. By 2015, Lenovo grew into the world's number 1 PC maker, number 3 smartphone manufacturer and number 3 in the production of tablet computers. In March 2017, Lenovo announced it was partnering with Fort Lauderdale, Florida–based software storage virtualization company DataCore to add DataCore's parallel I/O -processing software to Lenovo's storage devices. The servers were reportedly designed to outperform Storage Area Network (SAN) SAN arrays. In 2017, Lenovo formed

8418-526: The company agreed upon at this meeting was the Chinese Academy of Sciences Computer Technology Research Institute New Technology Development Company. The organizational structure of the company was established in 1985 after the Chinese New Year . It included technology, engineering, administrative, and office departments. The group first attempted to import televisions but failed. It rebuilt itself as

8540-480: The company hit $ 60 billion in annual revenues. On 8 October 2021, Lenovo withdrew its application to list on the Shanghai Stock Exchange just days after it had been accepted by the exchange, citing the possibility of the validity of financial information in its prospectus lapsing as the reason. The price of the company's shares on the Hong Kong Stock Exchange dropped by over 17% following the news, which

8662-438: The company publicly announced its new English name, "Lenovo", with an advertising campaign including huge billboards and primetime television ads. Lenovo spent 18 million RMB on an eight-week television advertising campaign. The billboards showed the Lenovo logo against blue sky with a slogan that read, "Transcendence depends on how you think." By the end of 2003, Lenovo had spent a total of 200 million RMB on rebranding. Lenovo

8784-600: The company rebranded itself to Lenovo, it acquired IBM 's PC business including its ThinkPad line in 2005, after which it rapidly expanded abroad. In 2013, Lenovo became the world's largest personal computer vendor by unit sales for the first time, a position it still holds as of 2024. Products manufactured by the company include desktop computers , laptops , tablet computers , smartphones , workstations , servers , supercomputers , data storage devices, IT management software, and smart televisions . Its best-known brands include its ThinkPad business line of notebooks,

8906-476: The company's early successes included the KT8920 mainframe computer. It also developed a circuit board that allowed IBM-compatible personal computers to process Chinese characters. Lenovo (known at the time as Legend) became publicly traded after a 1994 Hong Kong IPO that raised nearly US$ 30 million at HK$ 1.33 per share. Prior to the IPO, many analysts were optimistic about Lenovo. On its first day of trading,

9028-415: The company's international resources, such as its global sales channels and operation teams. These three elements have shored up our sales revenue in the past several years." The employees of the division, including those who developed ThinkPad laptops and Think Centre desktops, became employees of Lenovo. Despite Lenovo acquiring the "Think" brand from IBM, IBM still plays a key indirect, background role in

9150-488: The company's stock price hit a high of HK$ 2.07 and closed at HK$ 2.00 suggesting an initial under-valuing of the company. Proceeds from the offering were used to finance sales offices in Europe, North America and Australia, to expand and improve production and research and development, and to increase working capital. By 1996, Lenovo was the market leader in China and began selling its own laptop. By 1998 it held 43 per cent of

9272-481: The company. He will be paid in cash for 80 per cent of the shares and will receive 20 per cent in Lenovo stock. That would give him about one per cent of Lenovo. In September 2012, Lenovo agreed to acquire the Brazil -based electronics company Digibras, which sells products under the brand-name CCE, for a base price of R$ 300 million (US$ 148 million) in a combination of stock and cash. An additional payment of R$ 400 million

9394-616: The conference and both gave speeches on corporate governance. Lenovo sold its smartphone and tablet division in 2008 for US$ 100 million in order to focus on personal computers and then paid US$ 200 million to buy it back in November 2009. As of 2009 , the mobile division ranked third in terms of unit share in China's mobile handset market. Lenovo invested CN¥ 100 million in a fund dedicated to providing seed funding for mobile application development for its LeGarden online app store . As of 2010, LeGarden had more than 1,000 programs available for

9516-429: The design and production of the Think line of products. Today, IBM is responsible for overseeing servicing and repair centers, and is considered an authorized distributor and refurbisher of the Think line of products produced by Lenovo. IBM also acquired an 18.9% share of Lenovo in 2005 as part of Lenovo's purchase of IBM's personal computing division. In the years following the deal, IBM sold their stake in Lenovo, with

9638-678: The die over the ambient air can be calculated. The idea of thermal resistance of a semiconductor heat sink is an approximation. It does not take into account non-uniform distribution of heat over a device or heat sink. It only models a system in thermal equilibrium and does not take into account the change in temperatures with time. Nor does it reflect the non-linearity of radiation and convection with respect to temperature rise. However, manufacturers tabulate typical values of thermal resistance for heat sinks and semiconductor devices, which allows selection of commercially manufactured heat sinks to be simplified. Commercial extruded aluminium heat sinks have

9760-463: The domestic computer market share in China, selling approximately one million computers. Lenovo released its Tianxi ( 天禧 ) computer in 1998. Designed to make it easy for inexperienced Chinese consumers to use computers and access the internet, one of its most important features was a button that instantly connected users to the internet and opened the Web browser. It was co-branded with China Telecom and it

9882-414: The efficiency of the heat sink will decline. For semiconductor devices used in a variety of consumer and industrial electronics, the idea of thermal resistance simplifies the selection of heat sinks. The heat flow between the semiconductor die and ambient air is modeled as a series of resistances to heat flow; there is a resistance from the die to the device case, from the case to the heat sink, and from

10004-407: The emissivity in the visible spectrum is similar to the emissivity in the infrared spectrum; however, there are exceptions – notably, certain metal oxides that are used as " selective surfaces ". In vacuum or outer space , there is no convective heat transfer, thus in these environments, radiation is the only factor governing heat flow between the heat sink and the environment. For

10126-408: The epoxy is applied must be clean and free of any residue. The epoxy bond between the heat sink and component is semi-permanent/permanent. This makes re-work very difficult and at times impossible. The most typical damage caused by rework is the separation of the component die heat spreader from its package. More expensive than tape and epoxy, wire form z-clips attach heat sinks mechanically. To use

10248-515: The founders of Lenovo, indicated that the first meeting in preparation for starting the company was held on October 17 the same year. Eleven people, the entirety of the initial staff, attended. Each of the founders was a member of the Institute of Computing Technology of the Chinese Academy of Sciences (CAS). The 200,000 yuan used as start-up capital was approved by Zeng Maochao (曾茂朝). The name for

10370-515: The future around cloud technologies and their own POWER processor architecture. Lenovo's acquisition of IBM's businesses is arguably one of the greatest case studies on merging massive international enterprises. Though this acquisition in 2005 ultimately resulted in success, the integration of the businesses had a difficult and challenging beginning. Lenovo had employees from different cultures, different backgrounds, and different languages. These differences caused misunderstandings, hampering trust and

10492-425: The heat lost due to convection, the temperature of the fin and, therefore, the heat transfer to the fluid, will decrease from the base to the end of the fin. Fin efficiency is defined as the actual heat transferred by the fin, divided by the heat transfer were the fin to be isothermal (hypothetically the fin having infinite thermal conductivity). These equations are applicable for straight fins: where Fin efficiency

10614-404: The heat sink base, R b {\displaystyle R_{b}} , and the resistance in the fins, R f {\displaystyle R_{f}} . The heat sink base thermal resistance, R b {\displaystyle R_{b}} , can be written as follows if the source is a uniformly applied the heat sink base. If it is not, then the base resistance

10736-411: The heat sink to the ambient air. The sum of these resistances is the total thermal resistance from the die to the ambient air. Thermal resistance is defined as temperature rise per unit of power, analogous to electrical resistance, and is expressed in units of degrees Celsius per watt (°C/W). If the device dissipation in watts is known, and the total thermal resistance is calculated, the temperature rise of

10858-400: The heat sink's effective thermal resistance. To decrease the spreading resistance in the base of a heat sink: A pin fin heat sink is a heat sink that has pins that extend from its base. The pins can be cylindrical, elliptical, or square. A second type of heat sink fin arrangement is the straight fin. A variation on the straight fin heat sink is a cross-cut heat sink. A third type of heat sink

10980-404: The heat transfer between the heat source and the cooling fluid by conducting the heat current in an optimal manner. The two most attractive advantages of this method are that no additional pumping power and no extra heat-transfer surface area, that is quite different from fins (extended surfaces). The heat transfer from the heat sink occurs by convection of the surrounding air, conduction through

11102-425: The interface between the two materials. The selection does not include the cost of the material. Electrical resistivity may be important depending upon electrical design details. Light-emitting diode (LED) performance and lifetime are strong functions of their temperature. Effective cooling is therefore essential. A case study of a LED based downlighter shows an example of the calculations done in order to calculate

11224-422: The international norm of issuing quarterly reports. Lenovo created an audit committee and a compensation committee with non-management directors. The company started roadshows twice per year to meet institutional investors. Ma organized the first-ever investor relations conference held in mainland China. The conference was held in Beijing in 2002 and televised on China Central Television (CCTV). Liu and Ma co-hosted

11346-440: The laptop for performance and portability. Reviewers, however, praised the ultraportable. Notebook Review called it an "extremely fast ultraportable". However, they criticized the display colors and viewing angles. They also pointed out that the palm rest was prone to heating up because of the wireless networking card underneath it. The X61s was lauded for its excellent build quality, performance, and long battery life. The battery

11468-541: The last IBM-designed ThinkPads before Lenovo took over. The X41 tablet was designed by Lenovo. The X-series laptops released in 2006 by Lenovo were the X60, X60s, and X60 Tablet. The X60 and X60s slimline differed primarily by their processors: the X60s had a soldered low voltage processor, while the X60 did not. This gave the X60s a lower active temperature and longer battery life in exchange for reduced performance. The X60s also had

11590-443: The latter, the component must remain in thermal contact with its heat sink with reasonable shock and vibration. The heat sink could be the copper foil of a circuit board, or a separate heat sink mounted onto the component or circuit board. Attachment methods include thermally conductive tape or epoxy, wire-form z clips , flat spring clips, standoff spacers, and push pins with ends that expand after installing. Thermally conductive tape

11712-417: The market for Windows computers priced above $ 900 in the United States. Heatsink A heat sink is designed to maximize its surface area in contact with the cooling medium surrounding it, such as the air. Air velocity, choice of material, protrusion design and surface treatment are factors that affect the performance of a heat sink. Heat sink attachment methods and thermal interface materials also affect

11834-415: The other side of the clip can be placed in the other anchor. The deflection develops a spring load on the component, which maintains very good contact. In addition to the mechanical attachment that the z-clip provides, it also permits using higher-performance thermal interface materials, such as phase change types. Available for processors and ball grid array (BGA) components, clips allow the attachment of

11956-524: The required heat sink necessary for the effective cooling of lighting system. The article also shows that in order to get confidence in the results, multiple independent solutions are required that give similar results. Specifically, results of the experimental, numerical and theoretical methods should all be within 10% of each other to give high confidence in the results. Temporary heat sinks are sometimes used while soldering circuit boards, preventing excessive heat from damaging sensitive nearby electronics. In

12078-509: The reviewer admitted that the absence helps reduce weight. The laptops released in the X series in 2008 followed the new naming conventions established by Lenovo. The X Series laptops released by Lenovo in 2008 were X200 , X200t and X300 . The ThinkPad X200 was released on 15 July 2008. It leveraged the new technology from the X300, including the options of a solid-state drive (SSD), an optional integrated camera, 12.1 in (31 cm) widescreen display, optional 3G mobile broadband card,

12200-417: The simplest case, this means partially gripping a component using a heavy metal crocodile clip, hemostat , or similar clamp. Modern semiconductor devices, which are designed to be assembled by reflow soldering, can usually tolerate soldering temperatures without damage. On the other hand, electrical components such as magnetic reed switches can malfunction if exposed to hotter soldering irons, so this practice

12322-411: The smartphone market in 2012 and quickly became the largest vendor of smartphones in mainland China. Entry into the smartphone market was paired with a change of strategy from "the one-size-fits-all" to a diverse portfolio of devices. These changes were driven by the popularity of Apple's iPhone and Lenovo's desire to increase its market share in mainland China. Lenovo surpassed Apple Inc. to become

12444-508: The straight-fin it was 44 °C, or 6 °C better than the pin fin. Pin fin heat sink performance is significantly better than straight fins when used in their optimal application where the fluid flows axially along the pins rather than only tangentially across the pins. Cavities (inverted fins) embedded in a heat source are the regions formed between adjacent fins that stand for the essential promoters of nucleate boiling or condensation. These cavities are usually utilized to extract heat from

12566-478: The tablet features which have been executed with something close to genius". However, the high price tag and relatively inadequate performance were criticized by the reviewer. tabletPC Review acknowledged the sturdiness of the X61 tablet, the high battery life, and the quality of the pen. The features that met with disfavor were the lack of a widescreen, display brightness and colors, and the lack of an optical drive—although

12688-489: The temperature nodes shown in the diagram gives the following set of equations: where Using the mean air temperature is an assumption that is valid for relatively short heat sinks. When compact heat exchangers are calculated, the logarithmic mean air temperature is used. The above equations show that: Natural convection requires free flow of air over the heat sink. If fins are not aligned vertically, or if fins are too close together to allow sufficient air flow between them,

12810-435: The temperature of the device or component will depend on the thermal resistance from the component to the environment, and the heat dissipated by the component. To ensure that the component does not overheat , a thermal engineer seeks to find an efficient heat transfer path from the device to the environment. The heat transfer path may be from the component to a printed circuit board (PCB), to a heat sink, to air flow provided by

12932-456: The thermal conductivity does not take into account the interface resistances. Therefore, if a TIM has a high thermal conductivity, it does not necessarily mean that the interface resistance will be low. Selection of a TIM is based on three parameters: the interface gap which the TIM must fill, the contact pressure, and the electrical resistivity of the TIM. The contact pressure is the pressure applied to

13054-522: The thermal conductivity of aluminium, around 400 W/(m·K) for pure copper. Its main applications are in industrial facilities, power plants, solar thermal water systems, HVAC systems, gas water heaters, forced air heating and cooling systems, geothermal heating and cooling, and electronic systems. Copper is three times as dense and more expensive than aluminium, and copper is less ductile than aluminum. One-piece copper heat sinks can be made by skiving or milling . Sheet-metal fins can be soldered onto

13176-410: The thermal performance is at least 20% better than straight fin heat sinks. Lasance and Eggink also found that for the bypass configurations that they tested, the flared heat sink performed better than the other heat sinks tested. Generally, the more surface area a heat sink has, the better its performance. Real-world performance depends on the design and application. The concept of a pin fin heat sink

13298-544: The third-largest computer maker worldwide by volume. Lenovo's purchase of the Think line from IBM also led to the creation of the IBM/Lenovo partnership, which works together in the creation of Think-line of products sold by Lenovo. On the purchase of IBM's personal computer division, Chuanzhi said in 2012: "We benefited in three ways from the IBM acquisition. We got the ThinkPad brand, IBM's more advanced PC manufacturing technology and

13420-433: The threaded standoff and compression spring attachment method. A threaded standoff is essentially a hollow metal tube with internal threads. One end is secured with a screw through a hole in the PCB. The other end accepts a screw which compresses the spring, completing the assembly. A typical heat sink assembly uses two to four standoffs, which tends to make this the most costly heat sink attachment design. Another disadvantage

13542-613: The world's largest provider for the TOP500 supercomputers . In 2020, Lenovo became a preferred data center innovation provider for DreamWorks Animation starting with Trolls World Tour . On 12 January 2021, Lenovo filed an application to issue Chinese depositary receipts, representing newly issued ordinary shares, and to list them on the Science and Technology Innovation Board of the Shanghai Stock Exchange . In April 2021, Lenovo

13664-399: The z-clips, the printed circuit board must have anchors. Anchors can be either soldered onto the board, or pushed through. Either type requires holes to be designed into the board. The use of RoHS solder must be allowed for because such solder is mechanically weaker than traditional Pb/Sn solder. To assemble with a z-clip , attach one side of it to one of the anchors. Deflect the spring until

13786-622: Was an improvement over the X41. The model is one of the last to feature a 4∶3 aspect ratio display. Some X60s models shipped with the Intel Core 2 Duo L7300 clocked at 1.40   GHz or the L7700 clocked at 1.80   GHz. As of 2018, it was still possible to purchase new batteries and spare parts for these laptops from a few online retailers. The ThinkPad X61 tablet also received positive reviews, with IT Reviews saying that "the build quality and engineering are second to none and this shines through with

13908-439: Was bundled with one year of Internet service. The Tianxi was released in 1998. It was the result of two years of research and development. It had a pastel-colored, shell-shaped case and a seven-port USB hub under its screen. As of 2000, the Tianxi was the best-selling computer in Chinese history. It sold more than 1,000,000 units in 2000 alone. To fund its continued growth, Lenovo issued a secondary offering of 50 million shares on

14030-563: Was first used to refer to a layout of Chinese typewriters in the 1950s organized into groups of common words and phrases rather than the standard dictionary layout. For the first 20 years of its existence, the company's English name was "Legend". In 2002, Yang Yuanqing decided to abandon the Legend English name to expand beyond the Chinese home market. "Legend" was already in use worldwide by many businesses, making it impossible to register in many jurisdictions outside China. In April 2003,

14152-408: Was its biggest intraday decline in over a decade. "Lenovo" is a portmanteau of "Le-" (from Legend) and "novo", Latin ablative for "new". The Chinese name ( simplified Chinese : 联想 ; traditional Chinese : 聯想 ; pinyin : Liánxiǎng ) means "association" (as in "association of ideas"), "associative thinking", or "connected thinking". It also implies creativity. "Lianxiang"

14274-480: Was made dependent upon performance benchmarks. Prior to its acquisition of CCE, Lenovo already established a $ 30 million factory in Brazil, but Lenovo's management had felt that they needed a local partner to maximize regional growth. Lenovo cited their desire to take advantage of increased sales due to the 2014 World Cup that would be hosted by Brazil and the 2016 Summer Olympics and CCE's reputation for quality. Following

14396-498: Was now standard on all models. Up to 60   GB hard drives were available, and additional secondary "Extended Life Battery" could be purchased. X30 updated to the Intel Centrino platform, Pentium M CPUs, faster RAM (DDR PC2100), better GPU (ATI Radeon 7000) and more VRAM (16   MiB), USB   2.0, 2nd USB port on the left side, Gigabit LAN introduced on some models, IBM Security Sub System on some models. The first model in

14518-526: Was reorganized into three divisions: The Intelligent Devices Group for PCs, Smartphones, Smart Collaboration products, Augmented and Virtual Reality solutions and Internet of Things devices, the Infrastructure Solutions Group (formally known as Data Center Group) for smart infrastructure solutions, and the Solutions and Services Group focused on services and industry-specific products. That year,

14640-696: Was the first in IBM/Lenovo's long-standing X-series ultraportable line; the Celeron-based configurations had a thinner case. Same specifications as the X20, except an optional 600 or 700   MHz processor and more onboard RAM could be ordered. All new internal design, slim-version dropped, SVGA screen option dropped, Tualatin CPUs, faster (Mobility Radeon 7000 8   MiB) GPU, Communications Daughter Card/CDC slot, optional FireWire and/or WiFi on some models, 133   MHz FSB, maximum RAM increased to 640   MiB. Same as

14762-638: Was to become the world's largest maker of servers. Lenovo also announced plans to start integrating IBM's workforce. The acquisition added about 6,500 new employees to Lenovo. Lenovo said that it has no immediate intent to cut jobs. Lenovo said that positions in research and development and customer-facing roles such as marketing would be "100% protected", but expected "rationalization" of its supply chain and procurement. On 29 January 2014, Google announced it would sell Motorola Mobility to Lenovo for US$ 2.91 billion. As of February 2014, Google owned about 5.94% of Lenovo's stock. The deal included smartphone lines like

14884-495: Was to own a 51% stake in the joint venture, while NEC would have 49%. Lenovo has a five-year option to expand its stake in the joint venture. This joint venture was intended to boost Lenovo's worldwide sales by expanding its presence in Japan, a key market for personal computers. NEC spun off its personal computer business into the joint venture. As of 2010, NEC controlled about 20% of Japan's market for personal computers while Lenovo had

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