Are these power supply voltage fluctuations normal???

plb5114

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Feb 19, 2015
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I've recently installed two new solid state drives in my gaming PC and today I decided to use CPUID Hardware Monitor to check the voltages on my power supply. Upon running it I was surprised to see that the -12v rail is reading a voltage of -9.152v and the -5v rail is reading a voltage of -13.440v. To see how much they REALLY fluctuated, I went ahead and ran a stress test on the processor and graphics card. To my surprise they fluctuated even more to the numbers that you can see on the Max/Min columns in the picture attached below. I'm pretty sure this amount of voltage fluctuation on those two rails is definitely not normal but I'm not actually sure as I'm not an expert in electricity or power supplies. Could someone give me some insight and tell me what to do if these voltages are not normal. I am currently using a Corsair TX650W Power Supply for my PC. Thanks in advance!

Power%20Supply%20Voltages.jpg
 
Solution
First of all monitoring voltages using software (including BIOS) is unreliable. Second - > only look at the +12v rail -> any other readings are completely out of whack on all motherboards and PSUs i've tested (using software ofc).

+12v can sometimes be completely inaccurate as well but most of time time it provides at least some notion of whats happening on the 12v rails. By the looks of things you're doing fine at 11.97-12.16 (well under the allowed margin). The only way to test a PSU is by using professional tools that cost thousands of dollars or at the very least use a multimeter...

emdea22

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First of all monitoring voltages using software (including BIOS) is unreliable. Second - > only look at the +12v rail -> any other readings are completely out of whack on all motherboards and PSUs i've tested (using software ofc).

+12v can sometimes be completely inaccurate as well but most of time time it provides at least some notion of whats happening on the 12v rails. By the looks of things you're doing fine at 11.97-12.16 (well under the allowed margin). The only way to test a PSU is by using professional tools that cost thousands of dollars or at the very least use a multimeter...
 
Solution

plb5114

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Feb 19, 2015
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Thanks a lot guys. I did not know that. I appreciate the help and yes I kind of figured after thinking about it that if the voltages were really spiking like that something would definitely get fried. Thanks again!