Most likely, yes. If it's a POS power supply that has a peak of 400-450, then you may have some problems. Also, what is the Amps of the +12v rail on the PSU? There should be a sticker on the side that says "+3v@xA, +5v@yA, +12v@zzA". I need to know that the "zz" is on the +12v... off the top of my head, I think you need at least 26A combined to power an 8800, but I could be wrong.