CAn you explain a little bit more ?
I know the 6800 GS in AGP is not the same as the PCI-E version, but can you tell in numbers whats`s the difference ?
As stated, the default clocks are 350/1000 (AGP) and 425/1000 (PCI-E).
OC versions seem to top out at 400/1100 (AGP) and 490/1100 (PCI-E).
The difference is more than 10%. The stock clock difference is 17.4% (using 425 as a base, it's more the other way). With equal memory and pipelines, that means the speed difference should be 15%+. It's actually more than that though, closer to 25%.
Another difference is the core. The PCI-E is NV42 (which is 12-pipe native). Its supposed to be a more efficient design. The AGP version is NV40, a 16-pipe native design, with one quad disabled.
The AGP version comes out to being 25% slower than a 6800GT. Going by core/memory/pipelines, the 6800GT should be faster than the PCI-E 6800GS, but it's not. They are virtually tied.