Um... I actually had a 8600 sitting in another box... and it fixed it.
Another variable is that the HD4650 was using HDMI, the 8600 has no HDMI. Is this a driver issue, I know that ATI's have pretty crappy linux support? I may just buy a higher-end nvidia. Do you think this might also be fixed by switching over to the xorg ATI drivers?
Thanks for your help

Thanks for your help