‘Starting at the top, the biggest difference we see is a move from an nForce4-based SLI system to an ATI Xpress 200 CrossFire-based system sporting the new X1900 XTX GPU and the X1900 CrossFire cards. While this did increase the price of the graphics on the system, the fact was that even IF the NVIDIA 7800 GTX 512s had been in stock, they just aren’t as fast as ATI’s R580 core. Plus…they weren’t in stock. :)’
Source: PC Perspective
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