Question -11.68 on -12v — 14th PIN line

[dshort1988]

Hi there, I just tested a PSU and on the 14th -12v line it came back with a reading of -11.68. The rest of the PSU tested correct positive voltages. Is this normal?

Thanks in advance,
Dustin

 

[Ralston18]

Make and model PSU?

FYI:

https://www.lifewire.com/how-to-manually-test-a-power-supply-with-a-multimeter-2626158

-11.68 volts is within the + or - 10% tolerances per the ATX v2.2 link included in the table.


Reference - from the link:

Power Supply Voltage Tolerances (ATX v2.2)​

PSU Tolerance Table
Voltage Rail	Tolerance	Minimum Voltage	Maximum Voltage
+3.3VDC	± 5%	+3.135 VDC	+3.465 VDC
+5VDC	± 5%	+4.750 VDC	+5.250 VDC
+5VSB	± 5%	+4.750 VDC	+5.250 VDC
-5VDC (if used)	± 10%	-4.500 VDC	-5.500 VDC
+12VDC	± 5%	+11.400 VDC	+12.600 VDC
-12VDC	± 10%	-10.800 VDC	- 13.200 VDC

Is there a particular problem involved?

 

[dshort1988]

I can’t get a good look at the brand / wattage without taking the whole thing out. Great to know the tolerance ranges, I’ll be printing this out. The original board, customer was complaining about monitor turning off in the middle of gaming. Diag came back with the motherboard having a bad DMA controller. Swapped the board and now customer is complaining of restarts while gaming. I’m pretty sure the power supply is ok since everything is within tolerance and I’m considering caulking it up to a faulty replacement board. (It’s hard to find older boards brand new). For some odd reason my diag test won’t run on the replacement board in there now.🤷🏻‍. I do have another board on order. Thoughts? Maybe check temps?

 

[--SID--]

What are the full system specs includes the brand and model of the PSU?

 

[DSzymborski]

You can't properly test a PSU in this manner with a multimeter because it's all about the functionality at load. If you're *actually* testing a PSU properly and ruling it out, it means you used an oscilloscope and load tester. The very *first* thing that should have been done was evaluating whether the PSU had enough wattage *and* was of sufficient quality to even be appropriate for the hardware in question, and that involves knowing what the PSU is and the specific details of it in the first place.

 

[dshort1988]

Apevia 1000w gold plus — atx-pr1000w
i9 10900k
GeForce asus rtx 3060 ti
16 GB T force 3200mhz
Asus z490-v currently — replacing with Asus z490-p

Should be suitable. Maybe not the best brand? Is there a load tester someone would recommend? I’m going to try swapping the board again. I don’t have a load tester or scope.

 

[DSzymborski]

That's not as bad as most Apevias, some of which are pretty dire. I'd still at least swap it out with one I know is working, just to eliminate it. Still double-forward if I'm not mistaken and usually is in the "budget build" category in tier lists, certainly not an i9 machine. I tend to use my neighbor's old SunMoon; even entry level load testers of good quality will run $1500 and up, so it's a big investment.

 

[Misgar]

Typical programmable electronic load testers.
https://www.circuitspecialists.com/blogs/news/high-power-dc-electronic-load-testers

You might need more than one tester to check all the DC rails on an ATX PSU simultaneously.