CPU Bottlenecking at which range of GPU? (P4.266)

[Ashrym]

I have a P4 2.66 ghz/Asus P4C800 Deluxe Mobo. Which range of graphics cards will I start to see my CPU bottleneck at? I was thinking about going with and AGP X800GTO/GTO 2. I was considering the 6800 GS, but the AGP EVGA version on Newegg is $225, as opposed to the Sapphire X800 GTO for $165.

[NightshadowUK]

I'm pretty sure one thread is enough man.

*Link to original.*