ATI X800 XT PCI Express Review
 

The X800 XT is based on the GPU chip R420. The GPU is equipped with 16 pipelines, 4 per quadrant. You may be asking what is the difference between the X800 SE, X800 Pro, and the X800 XT? Well there isn’t much difference in the GPU. Since there are 4 pipelines per quadrant, ATI simply deactivates defective ones and sells it as a lower model. The X800 Pro has “12” pipelines. What this means is that one of the quadrants of an X800 XT is deactivated due to defective pipelines. If you look at an X800 Pro and X800 XT both built by ATI they will be physically identical. ATI uses the same HSF, PCB, and component placement on both models. AMD and Intel both use this same method of marketing when they have a CPU with defective cache. They simply disable the cache and re brand the CPU. This is how we get Celeron, Sempron, and Duron.

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