I've got the exact same card(came pre-installed in my PC) and have had nothing but problems with it, I'm replacing it soon. Until I looked into it here, I didn't know how much of a bad reputation this card has. Here's a thread I posted about it:-
If you wanna keep it, I would advise you to make sure you have a decent power supply - probably 400watts+ and also make sure you have the latest drivers. The catalyst drivers seem to have a bad reputation, but the Omega ones seem to be highly thought of. Don't have the link handy for them but I'm sure someone here will be able to direct you to those drivers.