I already had a fairly new 650 w PSU EVGA GQ gold, part of the same series even. Since I upgraded my graphics card I needed to upgrade my power supply. I figured I could just use all the cables that were in place and swap out the power supply. Well that wasn't the case since the pinouts are different. Luckily there's protection to prevent it from ruining anything. So learn from me, always replace the cables that come with the power supply even if they fit just fine! Amazing brand and products!