I have my 7750 running at 3.0ghz - with a Radion 5770 @ 900/1320, it calc'd out at ~12,500 (Mark06)
(MSI 780GX, 2x2gb Kingston HyperX, 500gb SATA WD green-label)
Personally I was a bit disappointed that it wasn't higher... but, I didn't O'C much at all. I've since returned my 5770 and plan to pick up a 460 when the timing's right.