HD 4850 Problems

In short my card will keep crashing after about 4-20 mins after logging in to windows. The popup is the standers ati driver has stopped working and has recovered it will do this about 2-3 times then freeze altogether. Having some limited experience with these matters i attempted to repair the problem but im now out of ideas. i took the following steps.

Rolling back the cards drivers
uninstalling then reinstalling the drivers
uninstalling CCC all together
Previous versions on CCC (remembering to wipe the registry and reboot)

any ideas ?

How long has it been doing this? What PSU and such is it running? HD 4850 is obviously in a different system to your current one in your sig?

Has it only recently started doing it? Have you tried the card in another computer? (If it is in another computer, try using it in the one in your sig and see what happens).

yeah its in another rig and its been doing this for about a week its running a 450w but before this it was fine. in my main rig it seems to be fine.

Try re-installing chipset drivers and all that.. Sounds like somethings conflicting with the ATI drivers. If it's only that computer, then I'd say the card is fine :\