The first in depth review I've found on the X800 PCIe version was put up by Chris Connolly. The most notable news is that it's clocked a bit slower than the AGP XTPE version. Assuming one could find one to buy (good luck), this would be the fastest PCIe card so far, and it uses a native PCIe implementation as opposed to a bridge chip. What is clear is that it will perform at about the same level as a 6800 GT yet cost half again as much. Looks to me like full on PCIe systems are still out there in the future. A person could put together a decent system, but they would pay considerably more than someone building either an A64 or 3.4C system with a 6800 ultra, both of which would smoke the PCIe system for gaming.
X800 PCIe review
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X800 PCIe review
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