I've been considering adding another 680 to my system, but am a little unsure of whether this would warrant a PSU upgrade as well. I'm currently using a Corsair HX650 which is getting on for a few years old now. All the other components would remain the same, namely: i5 2500k OC'd to 4.2GHz 3 x HDDs 1 x SSD 4 fans and 1 H60 for cooling My gut feeling is that it would be cutting it a little close, but that's not a very scientific way of deciding whether I need a new PSU or not. I'm not using any of those PSU calculator sites either as I know they're a load of rubbish. Any thoughts?