Low 5+rail: Motherboard or PSU Problem?

[Killrose]

I've noticed for the last 3-months or so that my 5+ rail is being reported lower than what I have kept a mental note of. It used to set at about 4.83 idle and as of late has worked it way down to 4.76 idle and I have seen it at about 4.63 running Prime. and had a crash the other day playing BF2 which I atributed to the 5+ rail probably runninig below the +/-5% spec.

So I did a close inspection of the caps for bulges and leaking as I still am running a NF2 Epox 8RDA and we pretty much all know about those problems
Anyway's I unplugged the 110AC to PSU and 20-pin PSU/motherboard connecter and cleaned out my CPU fan and others for 5min or so then fired it back up.

Now I'm seeing about 4.83 again and when running prime it does drop but not into the 4.63 arena and it has maintained this for the last 2days of intermitant checking, not steady run time. What do you think PSU or Mainboard?

 

[Peter]

4.7something, if the measuring can be trusted, is too low for stable operation. Looks like this PSU is plainly too weak for the mainboard and everything else combined.

 

[Killrose]

It is being taxed pretty heavily, I guess I could read the PSU 5+ rails at the 20-pin with a voltmeter and check it against what is being reported and then when I notice it drop check it again.

 

[Peter]

Yes, use a halfway calibrated volt meter for your own sanity. Careful, don't poke anything with the measuring tips.