Advice needed....

A lot of times with Psu's the capacitors go bad over time, especially if they weren't top of the line when new.

you can't take voltage as read in software as absolute, software is just not that good, you just kind of compare what you see now with what you saw the last time.

I'm battleing it out with what I think is a psu issue this evening, I have one card in an sli setup going to idle during a benchmark and killing my score.
this kit I have run many, many times so I well know how it behaves, like syrup on pancakes, it's always just ooooozzzzed sugary sweetness, tonight it's like chilli at waffle house, just yuck!!!!
the only thing new in the system is a fresh out of the box psu.

in this snip you can see that the cards are not doing squat, they should be at 1228 at default.

and there is the issue, my vantage, graphing dmm shows that the 12v rail has 250mV of ac on it and that is most likly causing my card to shut down.