New Hardware old PSU

[Toletero]

Hello.... I had a kinda old PC and I decided to upgrade... I bought a GYGABYTE ga-990fxa-ud3 and AMD FX 8320 processor, bought 2 8gb memory module... I had already in my PC a fairly new graphics card AMD Redeon HD 8xx serie, and 2 HDD of 500gb each... The only thing that I didn't change was the PSU.
The PSU is a 550w... I put everything together and it boot right up... I installed windows and as I was installing the drivers for all the different components the PC shuts off... Tried to boot up again and it didn't do anything, like it was dead... I took the cable to the PSU, off waited a few seconds, put it back in and started right up... 15 minutes later same thing happened, the PC shut off by itself... I did the paper clip test and the fan on the PSU turned but slowly and also one on the fan connected to the PSU. The PSU at no point got hot to the touch... I'm running Fanspeed and is not overheating... I have double checked every connector every component to make sure is sitting right but everything looks good... My question is ! The only thing that I have not changed is the PSU... Could it be that ?

 

[Karadjgne]

Kinda depends a lot on the gpu exactly and the psu exact model.

The HD 8950 is a 200w card. Add in 100w for mobo+accessories and 125w for cpu and you get @425w for the system. It's not entirely unheard of for a 550w psu to have an output of only 408w. After that, add in age of the psu, capacitors do loose ability over time, the best caps only loosing 2-3% per year, the worst loosing upto @10% per year, so it is definitely possible, if you have a low quality, 5yr old psu to have lost close to 50% of the psu ability. Even @30% loss would put a 550w at @375w, which is not near enough, as a HD8950 requires at a minimum of a 520w psu.

Sorry, but from what you described, it looks like the psu is just plain old and tired.

 

[Toletero]

Thank you very much for your input ! I will defenetly replace the unit tomorrow and tell you the outcome !