Testing older power supply +12V2 /single rail PSU

olack, Mar 24, 1:08am
Hi, why is my power supply tester warning a LL (low power I presume) on a +12V2 rail. I do not understand if the tester is showing a feature the power supply does not have in what I imagine is a single rail PSU in an older Net-Vista desktop PC. Can anyone explain what the +12V2 is and why it is showing a (LL)low voltage. This PC powers on but is not booting into Bios. Replaced low voltage 2.66V motherboard battery with a new battery but boot is the same, powers on with racing fan no beeps.

namtak, Mar 24, 10:01am
Buggered motherboard?


schizoid, Mar 24, 10:45am
possibly, but the OP is talking about their PSU. If it's reporting the wrong voltage when you test it, I wouldn't use it anymore.

olack, Mar 24, 10:48am
Testing the PSU yes. Yeah, testing for motherboard problem I think. PSU looks ok. My question is because I did not think this PSU should have any kind of +12V2 rail, and so should not expect to see any readout for a +12V2 in the PSU tester. Insides of the PSU looks good, no obviously damaged capacitors.

king1, Apr 22, 5:16pm
the obvious next step would be to replace the PSU.

I've had the odd situation where the PSU tester doesn't even report an issue yet replacing the PSU fixed the problem.

Share this thread

Buy me a coffee :)Buy me a coffee :)