angiosperms.doc

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IBM RoadrunnerRoadrunner is a supercomputer built by IBM at the Los Alamos National Laboratory in New Mexico, USA. Currently the world’s fastest computer, the US$133-million Roadrunner is designed for a peak performance of 1.7 petaflops, achieving 1.026 on May 25, 2008, and to be the world’s first TOP500 Linpack sustained 1.0 petaflops system. It is a one-of-a-kind supercomputer, built from commodity parts, with many novel design features.OverviewIBM built the computer for the U.S. Department of Energy’s (DOE) National Nuclear Security Administration. It is a hybrid design with 12,960 IBM PowerXCell 8i CPUs and 6,480 AMD Opteron dual-core processors in specially designed server blades connected by Infiniband. The Roadrunner uses Red Hat Enterprise Linux along with Fedora as its operating systems and is managed with xCAT distributed computing software. It also uses the Open MPI Message Passing Interface implementation. Roadrunner occupies approximately 6,000 square feet (560 m²)  and became operational in 2008.The DOE plans to use the computer for simulating how nuclear materials age in order to predict whether the USA’s aging arsenal of nuclear weapons is safe and reliable. Other uses for the Roadrunner include the sciences, financial, automotive and aerospace industries.Hybrid designRoadrunner differs from many contemporary supercomputers in that it is a hybrid system, using two different processor architectures. Usually supercomputers only use one, since such a design is easier to design and program for. To realise the full potential of Roadrunner, all software will have to be written specially for this hybrid architecture. The hybrid design consists of dual-core Opteron server processors manufactured by AMD utilizing the standard AMD64 architecture. Attached to each Opteron core is a Cell processor manufactured by IBM using Power Architecture technology. As a supercomputer, the Roadrunner is considered an Opteron cluster with Cell accelerators, as each node consists of a Cell attached to an Opteron core and the Opterons to each other.^[10]DevelopmentRoadrunner has been in development since 2002, and went online in 2006. Due to its novel design and complexity it was constructed in three phases and became fully operational in 2008.Phase 1The first phase of the Roadrunner was building a standard (albeit quite large) Opteron based cluster, while evaluating the feasibility to further construct and program the future hybrid version. This Phase 1 Roadrunner reached 71 teraflops and has been in full operation at Los Alamos National Laboratory doing advanced weapons simulations since 2006. Even if Roadrunner had not been greenlit for Phase 2, the Phase 1 form would still be a formidable supercomputer and would have ranked, at its time, in the top 10 list of the world’s fastest computers.Phase 2Phase 2 known as “AAIS” (Advanced Architecture Initial System) included building a small hybrid version of the finished system using an older version of the Cell processor. This phase was used to build prototype applications for the hybrid architecture. It went online in January 2007.Phase 3The goal of Phase 3 was to reach sustained performance in excess of 1 petaflops. Additional Opteron nodes and new PowerXCell processors were added to the design. These PowerXCell processors are five times as powerful as the Cell processors used in Phase 2. It was built to full scale at IBM’s Poughkeepsie, New York facility, where it broke the 1 petaflops barrier during its fourth attempt on May 25, 2008. The complete system was moved to its permanent location in New Mexico in the summer of 2008, where fine tuning of the applications will continue until final completion in the latter stages of 2009.Technical specificationProcessorsRoadrunner is unique for its hybrid design using two different models of processors.OpteronAMD Opteron 2210, running at 1.8 GHz. These are processors with two general purpose cores each. Opterons are used both in the computational nodes feeding the Cells with useful data and in the system operations and communication nodes passing data between computing nodes and helping the operators running the system. Roadrunner has a total of 6912 Opteron processors (6480 computation, 432 operation), for a total of (12960+864) 13824 cores.PowerXCellIBM PowerXCell 8i, running at 3.2 GHz. These processors have one general purpose core (PPE), and eight special performance cores (SPE) for floating point operations. Roadrunner has a total of 12,960 PowerXCell processors, with 12,960 PPE cores and 103,680 SPE cores, for a total of 116,640 cores.Number of coresOn the Top500 list, Roadrunner is said to have 122,400 cores. It is important to know which core is counted.

• 13,824 Opteron cores + 116,640 Cell cores = 130,464 cores for both the computing nodes and the operation nodes.

This is a number larger than the one mentioned on Top500. It turns out that the Roadrunner only used 17 Connected Units while doing the LINPACK benchmark, and it was not counting the cores in the operations and communication nodes (they didn’t run the benchmark).^[11]

• 6,120 Opteron (2 cores) + 12,240 PowerXCell 8i (9 cores) = 122,400 cores

TriBladeA schematic description of the TriBlade module.Logically, a TriBlade consists of two dual-core Opterons with 16 GB RAM and four PowerXCell 8i CPUs with 16 GB Cell RAM.^[7]Physically, a TriBlade consists of one LS21 Opteron blade, an expansion blade, and two QS22 Cell blades. The LS21 has two 1.8 GHz dual-core Opterons with 16 GB memory for the whole blade, providing 8GB for each CPU. Each QS22 has two PowerXCell 8i CPUs, running at 3.2 GHz and 8GB memory, which makes 4 GB for each CPU. The expansion blade connects the two QS22 via four PCIe x8 links to the LS21, two links for each QS22. It also provides outside connectivity via an Infiniband 4x DDR adapter. This makes a total width of four slots for a single TriBlade. Three TriBlades fit into one BladeCenter H chassis.Connected Unit (CU)A Connected Unit is 60 BladeCenter H full of TriBlades, that is 180 TriBlades. All TriBlades are connected to a 288-port Voltaire ISR2012 Infiniband switch. Each CU also has access to the Panasas file system through twelve System x3755 servers.^[7].CU system information:^[7].

• 360 dual-core Opterons with 2.88 TiB RAM.
• 720 PowerXCell 8i cores with 2.88 TiB RAM.
• 12 System x3755 with dual 10-GBit Ethernet each.
• 288-port Voltaire ISR2012 switch with 192 Infiniband 4x DDR links (180 TriBlades and twelve I/O nodes).

Roadrunner clusterA schematic overview of the tiered composition of the Roadrunner supercomputer cluster.The final cluster is made up of 18 connected units, which are connected via eight additional (second-stage) Infiniband ISR2012 switches. Each CU is connected through twelve uplinks for each second-stage switch, that makes a total of 96 uplink connections. Overall system information:

• 6,480 Opteron processors with 51.8 TiB RAM (in 3,240 LS21 blades)
• 12,960 Cell processors with 51.8 TiB RAM (in 6,480 QS22 blades)
• 216 System x3755 I/O nodes
• 26 288-port ISR2012 Infiniband 4x DDR switches
• 296 racks
• 2.35 MW power

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Alienware

Alienware is an American computer hardware company and a wholly-owned subsidiary of Dell, Inc.^[1] It mainly assembles third party components into desktops with custom enclosures for high-performance gaming. These products also support graphically intense applications such as video editing, simulation, and audio editing. Alienware also offers for sale rebadged laptops and computer peripherals, such as headsets, computer mice, monitors and keyboards. Alienware was founded in 1996 by Nelson Gonzalez and Alex Aguila. Alienware’s corporate headquarters is located in Kendall, Florida, an unincorporated area of Miami-Dade County west of the city of Miami.

History

Alienware headquarters in Kendall

Established in 1996, Alienware assembles high performance desktops, notebooks, and workstations. According to employees, the Alienware name was chosen because of the founders’ fondness for the hit television series The X-Files, hence the theme to their products, with names such as Area-51, Hangar18, m15x, and Aurora.^[2]

Alienware was originally established to tap a niche in the high performance game market, which back then was not on the radar of the major PC manufacturers such as Dell. Since high-end game hardware was not widely distributed, the company’s founders formed an OEM which sold personal computers with the highest performing hardware and settings according to benchmarks^{[citation needed]}. The company products are also differentiated by their sci-fi-based designs.

Acquisition and current status

Dell had been considering buying Alienware since the year 2002, but did not take any action until March 22, 2006, when it agreed to purchase the company.^[3] The new subsidiary maintained its autonomy in terms of design and marketing. However, Alienware’s access to Dell’s supply chain, purchasing power, and economies of scale would lower its operating costs.^[4]

Initially, Dell maintained its competing XPS line of gaming PCs, often selling computers with the same specifications. In hindsight, the XPS line may have hurt Alienware’s market share within its high end market segment. Due to corporate restructuring in the spring of 2008, the XPS brand has been scaled down. Many of the founders of Alienware have been moved from executive roles to product-development roles. Product development of gaming PCs has been consolidated with Dell’s gaming division, with Alienware becoming Dell’s premier gaming brand. It remains to be seen if this move will dilute the Alienware brand’s reputation for irreverence.^[5]

Operations

Alienware established its EMEA (Europe, the Middle East, and Africa) headquarters in Athlone, Ireland, in October 2002. As of FY As of 2005^[update], Alienware brought in upwards of $170 million USD in annual sales^[6] while undertaking an international expansion initiative launched in 2003 to maintain a presence in Australia, Canada, France, Germany, the United Kingdom, and Costa Rica. Alienware has had a self-owned and operated call center in Costa Rica to handle all sales and support calls for a number of years.^[7] The Alienware call center in Costa Rica has won numerous awards and has been the subject of study by industry insiders. Additionally, Alienware allows customers to send in old computer hardware in exchange for credit toward new hardware as part of their AlienExchange program.^[8]

Competitors

Alienware has traditionally competed with companies such as Sager Notebook Computers, AVADirect, Falcon Northwest, Puget Systems, Velocity Micro, and VoodooPC (which is now part of Dell’s largest competitor, Hewlett-Packard). Before being acquired by Dell, Alienware also competed against Dell XPS gaming systems

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The transmission electron microscope (TEM) operates on the same basic principles as the light microscope but uses electrons instead of light. What you can see with a light microscope is limited by the wavelength of light. TEMs use electrons as “light source” and their much lower wavelength makes it possible to get a resolution a thousand times better than with a light microscope.You can see objects to the order of a few angstrom (10^-10 m). For example, you can study small details in the cell or different materials down to near atomic levels. The possibility for high magnifications has made the TEM a valuable tool in both medical, biological and materials research.Magnetic Lenses Guide the Electrons
A “light source” at the top of the microscope emits the electrons that travel through vacuum in the column of the microscope. Instead of glass lenses focusing the light in the light microscope, the TEM uses electromagnetic lenses to focus the electrons into a very thin beam. The electron beam then travels through the specimen you want to study. Depending on the density of the material present, some of the electrons are scattered and disappear from the beam. At the bottom of the microscope the unscattered electrons hit a fluorescent screen, which gives rise to a “shadow image” of the specimen with its different parts displayed in varied darkness according to their density. The image can be studied directly by the operator or photographed with a camera.

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Number 1 ( 252 mph/407 km/h ) - Bugatti Veyron 252mph, 1001PS, 16 cylinders, four turbos, 8.0-litres… the Veyron’s numbers are staggering. It can hit 60mph in 2.5 seconds thanks to four-wheel-drive traction, shoots to 125mph in 7.3 seconds and reaches 200mph in less than 20. The Veyron 16.4 is the most powerful, most expensive, and fastest street-legal production car in the world , with a proven top speed of over 400 km/h.There can be no commercial logic behind such a crazy machine, even with the Veyron’s price tag of one million euros  

Number 2 ( 242 mph/395 km/h ) - Koenigsegg CCR

Koenigsegg’s design seeks to give an interpretation of strength and flowing motion. The body of a Koenigsegg is formed for one ultimate purpose - speed.The surfaces are shaped to perfectly aerodynamic, an appearance that does not deceive. All aspects of this machine serve its one fundamental objective. But the whale delivers a sense of power that you can’t find in its rivals either. Because of the targeted top speed, the body is designed to be so smooth that it has a very low drag coefficient of 0.30 Number 3 ( 240.14 mph/392 km/h) - McLaren F1

The McLaren F1 was the first production to use a complete carbon fiber chassis and body. Such lightweight construction, combined with the BMW S70/2, 620 horsepower engine, helped the McLaren achieve 240.14mph in its XP5 pre-production trim.The engine is a 6.1 litre quad-cam, 48-valve V12 which produces no less than 627 bph and a top speed of 231 mph

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How Big is RAM? RAM is small, both in physical size (it’s stored in microchips) and in the amount of data it can hold. It’s much smaller than your hard disk. A typical computer may come with 256 million bytes of RAM and a hard disk that can hold 40 billion bytes. RAM comes in the form of “discrete” (meaning separate) microchips and also in the form of modules that plug into holes in the computer’s motherboard.

 These holes connect through a bus or set of electrical paths to the processor. The hard drive, on the other hand, stores data on a magnetized surface that looks like a phonograph record. Most personal computers are designed to allow you to add additional RAM modules up to a certain limit. Having more RAM in your computer reduces the number of times that the computer processor has to read data in from your hard disk, an operation that takes much longer than reading data from RAM. (RAM access time is in nanoseconds; hard disk access time is in milliseconds.) Why Random Access?RAM is called “random access” because any storage location can be accessed directly. Originally, the term distinguished regular core memory from offline memory, usually on magnetic tape in which an item of data could only be accessed by starting from the beginning of the tape and finding an address sequentially. Perhaps it should have been called “nonsequential memory” because RAM access is hardly random. RAM is organized and controlled in a way that enables data to be stored and retrieved directly to specific locations. A term IBM has preferred is direct access storage or memory. Note that other forms of storage such as the hard disk and CD-ROM are also accessed directly (or “randomly”) but the term random access is not applied to these forms of storage. In addition to disk, floppy disk, and CD-ROM storage, another important form of storage is read-only memory (ROM), a more expensive kind of memory that retains data even when the computer is turned off. Every computer comes with a small amount of ROM that holds just enough programming so that the operating system can be loaded into RAM each time the computer is turned on. Here are some well known manufacturers ·        Kingston                                         ·        Corsair·        AZEN·         Crucial Prepared by:Abdulrahman Abdulaziz Alnasrullah

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