did you manage to update the bios to F09?.
The issue is not related to any problems with the supplied drivers. it is a known issue with the old bios, and the problem has been corrected in every instance by updating the bios.
Thats nearly always driver problem. Try uninstalling, then getting the most up-to-date ones off ATI's site. Make sure you do a reboot between uninstalling. Is this a laptop? If so.... the ATI drivers may not have the .inf for your laptop/card but seeing as its custom built hopefully no such problem?
aye; the problem seems to have receded almost entirely now. it still occasionally locks up, but the display drivers reboot fine on almost every occasion-this means its performance, despite the odd hiccup, surpasses my previous laptop sufficiently that i dont really mind haha...