This is quoted from another forum I like to visit.
https://www.pcvsconsole.com/forum/vie...tid=448&page=1
XBox vs. PS2
The CPU
Of course, the Central Processing Unit, the heart of every computer or console. Most of the calculations take place here. The XBox has a Intel processor which runs at a clock-speed of 733MHz. That's a lot higher than the 300MHz at which the PS2 CPU is running. But does that make the CPU better? Nope.
Here's why the PS2 CPU (Emotion Engine) is a lot more powerful:
-Data bus, cache memory as well as all registers are 128 bits on the PS2 CPU while the XBox CPU is 32 bits.
-It has a maximum performance of 6.2GFLOPS while the XBox CPU can only do a bit over 3 GFLOPS.
-It incorporates two 64-bit integer units (IU) with a 128-bit SIMD multi-media command unit, two independent floating-point vector calculation units (VU0, VU1), an MPEG 2 decoder circuit (Image Processing Unit/IPU) and high performance DMA controllers. Yes, this is all ON THE EMOTION ENGINE ITSELF.
Okay now what does this mean? It means that the PS2 can handle heavier physics and 3D engines (and can do more accurate realistic visual effects like splashing water and explosions). It also means that the PS2 can handle a lot more sophisticated Artificial Intelligence programming so that you have intelligent human-like opponents. And with a floating-point calculation performance of 6.2GFLOPS/second, the overall calculation performance of this new CPU matches that of a super computer. This is a completely new CPU architecture especially designed for sophisticated graphics and physics while the architecture of the XBox CPU is pretty old and simple and looks a lot like the architecture of the 486 CPU from back in the early '90s. The architecture of the Emotion Engine really is very sophisticated so I'm not going to explain it in detail here. But simply put the main advantage of the PS2 CPU is that it is subdivided into lots of other tiny powerful processors, all of them designed to do a special task and almost all of them can work independently from each other.
And another thing... the processor inside the box does not say "Pentium III" anywhere. It simply reads "Intel". The XBox's processor is NOT an Intel Pentium III, as Microsoft would have you believe, but in fact a Celeron II. It is a 700mhz Celeron, complete with 128kb of L2 cache (P3 coppermines actually have 256kb L2 cache), but overclocked to a 133mhz FSB, resulting in PIII/Celeron hybrid. What makes it a Celeron II is the fact that it is still using a Coppermine Core, with 8 way set associative L2 cache rather than your typical Celeron 4 way set Level 2 cache. What it ultimately comes down to is that this Coppermine core, which allows Microsoft to market the XBox as a PIII Coppermine, is about a 10% speed increase over the Celeron equivalent of this processor. Is the XBox CPU a Celeron? Not really. Is it a Pentium III CPU in the sense that everyone thinks of a PIII Coppermine? Nope. It's somewhere in between.
The Graphics Chip and VRAM
This is where the images are rendered. The XBox uses an Nvidia Graphics Processing Unit running at 250MHz and the PS2 uses the Graphics Synthesizer running at 150MHz. Again, judging by these specs the XBox looks better. The XBox GPU has a few advantages (or maybe not) over the PS2 GS, for example:
-The XBox GPU can do 125 million polygons while the PS2 GS can only do 75million polygons
-The XBox GPU has a max. Resolution of 1920x1080 and the PS2 GS can do 1280x1024 The rest of the graphics chip will be comparable to NV-20 chip, there are a lot of neat effects the XBox GPU can do with its hardware, but all those effects can be done by the Emotion Engine in software too (while the XBox' CPU is not powerful enough to do complex visual effects in software).
But the catch is that these advantages (talking about higher resolutions here) don't make a lot of difference on a TV screen, even on an HDTV screen the difference would be barely noticeable (when the console's hardware is used properly). So, is the XBox Graphics Processing Unit better than the PS2 GS? It doesn't look like it, the architecture of the PS2 GS looks far more advanced. For example, PS2 has a parallel rendering engine that contains a 2,560-bit wide data bus that is 20 times the size of leading PC-based graphics accelerators. The Graphics Synthesizer architecture can execute recursive multi-pass rendering processing and filter operations at a very fast speed without the assistance of the main CPU or main bus access. In the past, this level of real-time performance was only achieved when using very expensive, high performance, dedicated graphics workstations. There is a 48-Gigabyte/sec memory access bandwidth achieved via the integration of the pixel logic and the video memory on a single high performance chip. The quality of the resulting screen image is comparable to high quality pre-rendered 3D graphics. (that is once the game developers have learned how to use it properly) There has also been a misunderstanding about the VideoRAM on the PS2. The VRAM is included in the 32MB of main RAM on the CPU (the developer chooses how much of it he wants to dedicate to VRAM). Everyone thought the 4MB of memory on the GS was the VRAM while that is just a buffer in which all the rendering is done so no external bandwidth is needed (only for texture streaming). Another rumor that's been spread by several gaming sites is that the XBox is capable of texture compression and full scene anti-aliasing while the PS2 isn't. This is simply not true. The PS2 can compress/ decompress textures and do full scene anti-aliasing without causing as much slow-down as on the XBox. And although the XBox GPU can do a lot of effects that are not 'built-in' in the PS2 GS, the PS2 can do all these effects and more in software mode (but at least at the same quality) through the Emotion Engine.
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