How to check PSU is performing good or not ?


Broken In
Hi, is there any way to check your PSU ?
weather a reputed PSU is showing any signs of failure on any of the 5.5/12V/3V outputs ?

I have a multi meter, and knows to start a PSU by shorting green and ground cable.
Is it possible to check the ripple filtering levels and power aspects, without killing the PSU ?
What else needs to be checked?

Please share the link/keywords if there is a specific thread t discuss this..


Ambassador of Buzz
as per my limited knowledge and experience...

you cannot check ripple , you need oscilloscope for that.

you can check voltages using multimeter and see if they are ok at both idle and during load.. watch a few youtube videos first before attempting..

atx allows 5% deviation .. so 11.4-12.6v for 12v and 4.75-5.25v for 5v is safe range.. ideally they should not exceed 3% but during heavy crossload or during very low loads voltages can be closer to 5% limits

but it is better to not stress test or heavily load these old psu.. doing this may easily accelerate their aging a lot and can possibly damage something if it already had started going bad

what you can do at most except checking voltages is

first you can look up your psu model number and google if any internal images of psu are available..
and look at capacitors brand and series which it belong to.. to get rough idea of how long do they last on

if you can see clearly through psu fan
look at capacitors .. and carefully give all capacitors a look and see if any of them is bulging or leaking..

Warning- opening psu is dangerous , those main big cap contains upto 400v and can very seriously shock you if you are not careful and if they haven't been discharged .. DO NOT do it if you are inexperienced/uncomfortable
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