No, unless it is a good brand such as a Seasonic or Corsair, or something of a similar build..  I fried a 500 Watt PS that was a cheap one, I forget the brand, and all I had was a Gigabyte 7950.
It worked fine while I mined for 1 month, then just burned out.  no OC or anything.


(Someone posted while I was typing this, but in essence, +1 for the answer.)