Bad PSU with good voltages?

leSLIeX

Junior Member
Mar 25, 2019
6
1
11
Thinking that my old mobo was faulty, because it was freezing and rebooting randomly, I recently bought new parts ( except for the Corsair 850HX PSU and GTX 980Ti Vid card ) but the random rebooting problem persisted (although not as often as before). So I bought a new Seasonic 1000W PSU and problem solved (yeah, 1000W might be a little overkill :smile:)

According to HWmonitor and some other programs, the Corsair 850HX voltages appear to be good, they appear to be within ATX tolerance (± 5% ). The PSU, is only 3,5 years old and it doesn't have warranty (sold overseas, so no warranty :weary:).

So, could the PSU have good voltages but still under load be faulty? And if so, could the PSU be fixed? It's not like a rectifier diode is burned, it would be more complicated than that... I wouldn't like to throw it away just yet.
 

UsandThem

Elite Member
May 4, 2000
16,068
7,380
146
The only way (not including professional equipment) to get the true voltages for a PSU is with a multimeter. They might look normal with readings in various programs and such, but they could differ quite a bit otherwise. It could be something as simple as a bulging capacitor or other component that causes a momentary issue.
 

leSLIeX

Junior Member
Mar 25, 2019
6
1
11
The only way (not including professional equipment) to get the true voltages for a PSU is with a multimeter. They might look normal with readings in various programs and such, but they could differ quite a bit otherwise. It could be something as simple as a bulging capacitor or other component that causes a momentary issue.

Oh, I see. I will use a multimeter then. I'll report back my findings
 
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mikeford

Diamond Member
Jan 27, 2001
5,667
157
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Multimeter IMHO is close to useless, really not of any more value than a diagnostic cards with LEDs showing voltage status. Typical meters measure STATIC conditions, resets and reboots are due to more like glitches, very brief out of spec voltages some kind of tracking and limit checking system is needed..

Hard to argue with, system works with PS A and not with PS B. Maybe try another system, but the PS would remain suspect one to me.
 

Confirmation

Member
Apr 25, 2019
61
5
11
whats the 3v and 5v voltage in the first PSU, and whats in the second one

whats your setup

i totally not recommend coolermaster PSUS, i had a terrible bad experience of just 1 year of use each one in 500w 600w 850w versions (burned inside, and sometimes i saw an insect radioactive insect or something O_O outs of the capacitor wtf)

ill recommend you EVGA and STRIKE X aerocool, both 5 years + still running 0 problems
 

Confirmation

Member
Apr 25, 2019
61
5
11
Spider-Man? :oops:

i dont know what it is tryied to find it in google but i didnt found nothing, they are brown! O_O i have all the PSUs in a bag, im sure if ill open it, that strange insects will be there, feeding of the material inside the capacitors o.o
 

Modular

Diamond Member
Jul 1, 2005
5,027
67
91
Multimeter IMHO is close to useless, really not of any more value than a diagnostic cards with LEDs showing voltage status. Typical meters measure STATIC conditions, resets and reboots are due to more like glitches, very brief out of spec voltages some kind of tracking and limit checking system is needed..

Hard to argue with, system works with PS A and not with PS B. Maybe try another system, but the PS would remain suspect one to me.

I agree here. One thing to consider is that a PSU needs to supply much more than voltage; it needs to be able to supply a steady amount of current as well. Your PSU may show the proper voltage, but be unable to keep up with the amperage (current) demand that your computer is requiring. Often times "ripple" in the current can cause instability as well.

Without some pretty sensitive diagnostic equipment, it's hard to tell what's at fault. I'd go with the fact that you can change out the PSU with no issues as enough proof that the PSU is dead (dying).
 

Rifter

Lifer
Oct 9, 1999
11,522
751
126
Its totally possible, a MM will only tell you voltages, what you really want to see is what happens to those voltages under load, so you need a load tester and ideally a scope to fully test a PSU.