Quote Originally Posted by Starlord View Post
Well, naturally you want to have a 100-200 watt cushion to what your whole computer can handle.

1200 watts is plenty and you can never go wrong with more watts :P, good for when you want to upgrade. However, a Good 900 Watt (Gold) will be decent enough for the card + computer .
Even though a 1200w should be plenty, it also depends on the design of the PSU. Is it a single rail, multi-rail... model# would be helpful. But with that said, I highly doubt the PSU is the main issue. Although the only way to tell is to have it tested.