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Question on voltages: -12v

post #1 of 4
Thread Starter 
I'm having trouble finding any info on what the -12v rating in HWMonitor is supposed to mean and wondered if it could be the cause of my PC woes.

While all my other voltages min/max are within 10%~ of each other, the -12v is all over the place and constantly fluctuating:
Minimum reading: -13.70v
Maximum reading: -3.90v

Is this normal for it to read like that?

Trying to identify the source of my graphic crashes in-game. I've ruled out a bad GPU and am looking at the next step.

Thanks!
post #2 of 4
-12v is rarely present and rarely needed in modern PCs. The newest thing I can think of that might need them is a serial port.

In general, you can ignore the reading for it, because even if it's accurate (and it's often not), it's almost certainly not the cause of your problems.
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CPUMotherboardGraphicsRAM
5820K @ 4.3GHz, 1.225v Gigabyte X99 SOC Champion (F4m) 2x Sapphire R9 290X Tri-X OC New Edition (10036... 4x4GiB Crucial @ 2667, 12-12-12-28-T1, 1.35v 
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CPUMotherboardGraphicsRAM
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CoolingOSPowerCase
Prolimatech Genesis + 2x140mm Cougar 1200rpm Windows Server 2008 R2 Antec TP-750 Antec P182 
Audio
ASUS Xonar DS 
CPUMotherboardGraphicsRAM
FX-9590 @ 5GHz, 1.55v ASUS Sabertooth 990FX R2.0 Reference NVIDIA GTX 780 2x8GiB G.Skill DDR3-1866 10-11-10-30-T1, 1.5v 
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post #3 of 4
It's always been normal for the negative voltages to be way off. I think the tolerance for them is +- 10%, but +- 20% variation isn't unusual.

-5V and -12V were originally used to bias some chips, but all chips generate those voltages internally now. I think the last chips that needed negative voltage were some sound processors (ot just for bias).

Even RS-232 serial ports quit taking -12V and +12V directly from the PSU a long time ago but generate those voltages from the +5V, and that was done even with a vintage 1997 motherboard I had.
post #4 of 4
It isn't used for anything on modern systems, except maybe some really, really cheap RS232 PCI cards.
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