Low 12 volt rail

a computer of mine keeps randomly shutting off, then turning back on and loading back in. it does not tell me that windows has not shut down correctly or anything.

i suspected 2 things


checked the temps, all good

checked the psu with my psu checker, all good. looked in bios, and the 12v rail was at like 11.1-11.3.

is that voltage acceptable, and it was jumping around there ALOT.
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  1. Best answer
    You should use a DVM to check it, but 11.1-11.3V is out of specs. It should be 11.4-12.6V and relatively stable.
  2. Brand / Model ?
  3. That voltage would be out of range, but I would check it with a digital multimeter first. Software and BIOS readings are somewhat notoriously unreliable.
  4. Like the other posters above said, "11. - 11.2 volts is out of tolerance." But is is probably worse than you think. Remember, a PSU tester puts a minimal load on a PSU.

    Borrow a meter and check between the yellow and black wire on a drive molex power connector while the PSU is running.

    With a little over 11 volts, a good PSU would not have let you boot.
  5. tolerance on a psu is 5%, so you should have 11.4 v +.....also, check you heatsink and you have thermal paste under the heatsink or the fan running properly
  6. Full system specs might help to see if you're overloading your PSU, and also its brand and model to help determine overall quality.
  7., the first post answered my quest. and as far as overheating, its not. and i own a DMM, 3 actually, im not a tech noob. and the voltage i posted was already checked with my multi meter.
  8. If it's reading <11.4V with a digital multimeter, it's out of spec and should be replaced.
  9. Best answer selected by skikarl.
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