Nvidia Geforde 6600 and Computer Freezing

I have a problem... I recnerly build a new computer and I have spent an extra 300 dollars trying to fix a problem. My computer keeps freezing randomly, and it only happens when i plug the molex into my video card. It is not the stock molex, but instead one from my psu. I was told that this wasn't a problem. But anyhow, the freezing got annoying so i just unplugged it, and i would like to get rid of that annoying nvidia popup, and I would like even more to have my computer running perfectly. Im not much for information, so I have attatched an everest log... Oh abd btw i have a 500w psu (boucht recently), all the latest drivers, etc.