I just got my Sapphire 9800 Pro from Newegg this week and with the Artic Cooling Silencer and some home made ramsinks I'm at 485/385 right now and she has some more room left in her. Just waiting on my Mobile 2500+ (which will be here on Monday). Just to give you an idea of what other people are getting for OC's. Hope this helps.
Amd Athlon 3200+, DFI NFII Ultra Infinity, 1 gig Corsair Dual Channel, 9800 Pro @ 455/370
3DMark2001se <font color=red>18208</font color=red>
3DMark2003 <font color=red>6350</font color=red>