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An illustrated Guide AMD K7 Athlon. Both copper and aluminium chips available. The Thunderbird is a very powerful chip with its 37 million transistors. It competes directly with the Pentium III "Cumine". The "old" Athlon design using a Slot A-based cartridge suffered from poor L2 cache performance. The 512 KB of L2 cache was placed outside the CPU. This gave a connection to the CPU working at only a half or a third of the processors clockspeed. Integrating the L2 cache with the processor, the 256 KB is accessed at full processor speed, as it should. On-die cache gives the best performance. The reduction in the L2 size from 512 to 256 KB is of less importance; the full clockspeed has an enormous effect. The Thunderbird chip performs just as good as or slightly better than Pentium III running at the same clock frequencies. With the new on-die L2 cache of 256 KB in combination with the original 128 KB L1 cache, AMD indeed has a very powerful product. Narrow L2 cache to CPU pipeline Still Pentium III Cumine has one advantage to the Thunderbird. When Intel decided to integrate the 256 KB of L2 cache with the processor, they gave it a 256 bit wide bus to work with. When the L2 resides outside the CPU you have to stick to a 64 bit bus between CPU and L2. This restriction comes from the number of CPU pins you want to allocate to the L2 connection. If the L2 cache is integrated with the CPU there is no need for this limitation. Intel wisely went from 64 to 256 bits width. This AMD has not done. For some reason, the Thunderbird core still only connect to the L2 cache on a 64 bit wide bus. Copper or alu? The new Thunderbirds are being produced two fabs: At fab25 in Austin, Texas (0.18 micron aluminium) At fab30 in Dresden, Germany (0.18 micron copper) AMD told that there should be no difference between the two chips. Copper is the most sophisticated material since it opens up for much higher clock frequencies than aluminium, due to the better electrical conduit. However, at sub-GigaHertz frequencies aluminium works fine, and there should be no difference between the chips coming from different fabs. http://www.karbosguide.com/hardware/module3e08b.htm (3 of 5)7/27/2004 4:08:43 AM An illustrated Guide AMD K7 Athlon. Chip sets Please support our sponsor. The original Athlon chip set AMD 750 works fine with the Thunderbird processor. However, AMD is soon introducing the 760 chipset for use with Thunderbird. It is expected to support DDR RAM. The popular VIA KX133 chip set had problems with Thunderbird. Therefore VIA produced the KT133 chipset specially designed for Thunderbirds and Durons. This chipset was at first introduced as "KZ133" which was a very unwise choice in naming. KZ was the Nazi-German abbreviation for concentration camp - the camps in which millions of Jews and other Europeans were murdered. VIA wisely renamed the chip set when the historical significance of the two letters KZ came to their minds. Another brand of Athlon is the "Spitfire" core, which was launched as "Duron" for cheaper PCs - Celeron-killer so to say. Please see module3e13 on this chip. Sledgehammer Please support our sponsor. The successor to Athlon is codenamed "Sledgehammer". It sounds interesting: Multi-core technology with several complete microprocessors working parallel within the same CPU. The IA32 set of instructions are beeing extended to include a 64 bit mode. More powerfull FPU. The value of 64 bit instructions is disputeable. We already have 64 bit and even 128 bit instructions within SSE and 3DNow!. Here it means new 64 bit instructions, registers, busses and memory addresses. To benefit fully from this 64 bit power, all software have to be recompiled. But AMD claims that the processor will run all existing 32 bit software at full speed as well. From my humble viewpoint, "Sledgehammer" (what a name) sounds far more interesting than Intel`s Itanium. Backward compatibility has always been extremely important. Lots of RAM http://www.karbosguide.com/hardware/module3e08b.htm (4 of 5)7/27/2004 4:08:43 AM An illustrated Guide AMD K7 Athlon. One of the limitations of the 32 bit architecture is the amount of RAM. A 32 bit processor can "only" address 4 Gb of RAM. This is not enough for the biggest systems. With 64 bit addressing you can use 18 Exebytes of RAM. That`s a lot. Sledgehammer will be introduced in 2002. Please also see the article on die sizes here. Next page Previous page Learn more [top] Read about chip sets on the motherboard in module 2d Read more about RAM in module 2e Read module 5a about expansion cards, where we evaluate the I/O buses from the port side. Read module 5b about AGP and module 5c about Firewire. Read module 7a about monitors, and 7b on graphics card. Read module 7c about sound cards, and 7d on digital sound and music. [Main page] [Contact] [Karbo`s Dictionary] [The Software Guides] Copyright (c) 1996-2001 by Michael B. Karbo. www.karbosguide.com. http://www.karbosguide.com/hardware/module3e08b.htm (5 of 5)7/27/2004 4:08:43 AM An illustrated Guide to 6th generation CPUs Please click the banners to support our work! KarbosGuide.com. Module 3e.09 On MMX, 3DNow!, and Katmai The contents: An introduction The FPU Working with 3D graphics MMX 3DNow! Katmai Multimedia, MMX and Katmai Next page Previous page [top] http://www.karbosguide.com/hardware/module3e09.htm (1 of 6)7/27/2004 4:08:45 AM An illustrated Guide to 6th generation CPUs With the Pentium MMX we had the first of several improvements of the microprocessor`s set of instructions. Later, we got 3DNow! and Katmai. What does all this mean? In 1995 the Pentium processor was expanded with the so-called MMX instructions. That was announced as a multimedia expansion with 57 new instructions. Today the emphasis in multimedia is especially in 3D graphics. Here the most important operation is the so-called geometric transformations, which deal with floating-point numbers. Let us take a look at these issues. FPU [top] FPU stands for Floating-point Unit. That is the unit in the processor, that handles floating-point numbers. It is difficult for the CPU to manipulate floating-point numbers, since it requires lots and lots of bits to perform an accurate calculation. Math with integers is much simpler, and is done with hundred percent accuracy each time. The FPU works with floating - point numbers of various bit length, depending on the desired degree of accuracy. The most accurate type has a bit length of 80! All the modern P6 processors have 8 FP registers, each of which has a bit length of 80. So there is room inside the CPU itself for 8 numbers each of 80 bit length or, for example, 16 numbers each of 32 bit length. Read more... Working with 3D graphics [top] Please support our sponsor. When you draw people and landscapes, which are altered in 3D graphics, the figures are built up from small polygons (usually triangles or rectangles). A figure in a PC game can typically be built from 200-1500 such polygons. For each change in the picture these polygons have to be re-drawn in a new position. This means that each corner (vertex) in every polygon has to be recalculated. Floating-point number operations ... - tailieumienphi.vn
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