Testing PSU

Muel · 3 Jul 2010 at 08:40

Hello there,

I'm having some instability issues. They were happening fairly irregularly, but getting far more regular as if something was dieing, after some testing I decided it was most likely the motherboard, so replaced it. Everything was fine for a couple of days. Now it is crashing again, although very infrequent.

I'm worried that the PSU is dodgy and killed the old board, what are the chances of this, and how can I test my PSU?

Anything else it could be? It's always the same crash, Windows locks up. The only change is sometimes the cursor is still free to move around, sometimes it's free until i reboot, sometimes it's free for a short time then locks up.

Here are my PSU voltages from HWMonitor:

+3.3v: MIN:3.34v MAX 3.34v
+5v: MIN: 4.95v MAX: 4.97v
+12v: MIN: 12.22v MAX: 12.22v
VBAT: MIN: 3.18v MAX: 3.18v

Are these anything to worry about? To me the +5 is too low and the +12 is way too high?

No idea what the VBAT is though.

By the way, ran 1 pass of Memtest from a pen drive, 0 errors. Does it need to be for several passes or is one OK?

Tealc · 3 Jul 2010 at 09:14

ATX 2.2 Spec said:
4.1.4 Voltage Tolerances
Tolerance for the motherboard power rails should comply with the values listed in Table 6.
Table 6. Voltage Tolerances
Voltage Rail Tolerance
+5VDC ± 5 %
-5VDC (if used) ± 10 %
+12VDC ± 5 %
-12VDC ± 10 %
+3.3VDC ± 5 %

So 10.8v/13.2v would be acceptable on the 12v rail? The Voltage regulators will take care of any slight differences such as .22v.

HWMonitor has my 12v down as 1.23v, that's clearly not correct.

stulid · 3 Jul 2010 at 09:16

you or your sig don't mention which psu it is?

RJC · 3 Jul 2010 at 09:41

I would, if possible test the voltages with a multimeter.

As I don't really trust software reading voltages, mine shows up as 6v on 12v line, 1v on the 5v line.

Muel · 3 Jul 2010 at 12:39

I have a multimeter, no idea how to test it though. Any guides or anything knocking about?

It's a corsair HX650W (I think, it's the non-modular one anyway. The sticker is yellow.)

JW1993 · 3 Jul 2010 at 23:57

I seen a PSU tester somewhere not so long ago but I can't remember where :confused:

but atleast I'm sure you can get them!

robinbredin · 4 Jul 2010 at 11:36

Is this any good to you HERE.

wilko49 · 4 Jul 2010 at 12:08

HWMonitor isn't very accurate, my 12V rail reads at 8.1V max, 3.1V min, multimeter shows it pretty consistent at 12.21V.