Spent this evening benchmarking my brothers old ATi X550 256mb in my E6400 (2.13Ghz) @ 2.408Ghz. I was able to boost the FSB on the E6400 by 5 after the 3D Mark 05 test, but it made no difference to the previous tests.
The X550 overclocked quite well on air - from 450/277 to 480/342, using ATi Tool auto-tune settings.
CPU: Intel Core2Duo E6400 (2.13Ghz) @ 2.448 Ghz
GFX: ATi X550 256mb (450/277) @ 480/432
WD Raptor, 2GB Ram @ 5-5-5-13 382.5*2
35108 on Aquamark (6th)
16470 on 3D Mark 01 (17th)
4527 on 3D Mark 03 (8th)
2330 on 3D Mark 05 (7th)
641 on 3D Mark 06 (5th )
Tomorrow, I intend to work on the X800XL I have. Initial findings show it doesn't overclock well.
Check out my HWBot.org profile.