hd5850 oc screw up?

hd5850 oc artifacts. need help!

guys i have an xfx hd5850 xxx edition which has its stock clocks
@ 755 / 1000. i had a stable oc for about a year @ 815 / 1096. recntly I
installed battlefield 3 and every time i run it a popup came that suggested me to update
drivers to 11.10 from what i think it was 10.4. so i did update but i couldnt see my fps stack at 22. so i oced further more @ 920 / 1200 an voltages from 1089 to 1125. and it was stable. but on the next attempt @ 950 / 1200 / 1125v. i had artifacts during testing. and i mean random pixels across the whole screen with different colors than they should. normal right? when i exited furmark the artifacts remained on everything i did. i tried roll back of the drivers, underclock to the previous 2 stable ocs and even below stock and nothing happened. any ideas?

Did you reboot? I doubt you've smoked the card, I've pushed an XFX BE HD5850 in my other PC to 1000/1200 @1.25v and it's still running like a champ for over a year now.

yes i rebooted after every action i took. i also doubt that i fried it because the temps never passed 67 celsious. the strange thing is that when i change wallpaper the artifacts are reduced alot but they slowly come back


edit:
just an update if it helps i uninstalled catalyst and then went on my computer - manage - device manager - display adapters and uninstalled the
drivers and the artifacts disappeared. i rebooted and installed the latest catalyst drivers 11.11 and the artifacts came back. what should i do?

c'mon guys nobody has any clue about solving this problem?