Question Loud pop sound from replaced power supply


Sep 8, 2017
I'm running W10 on a 1st Gen i7 from Dell. Model 435MT.
I bought a used power supplly unit fom a repair shop. I installed it and powered on the computer. A loud pop sound came from the PSU but the computer runs fine. I didn't smell anything and it has been running fine for over 24 hours with no other symptoms except that I had an old 2008 hard drive go out in the same computer after I powered down the computer and turned it back on. The cable that the HDD was connected to also had an SSD but the SSD is perfectly fine. I suspect the HDD had something to do with that pop but even after the popping sound, that HDD ran long enough for me to copy all the data that was on it. Odd luck huh?

So, just to recap. I replaced the old PSU, nothing else changed. Heard a pop. Computer runs fine. Backed up the data on the HDD. Powered the computer on and off about 10 times. On the 11th power on, the system hung or booted slowly due to the HDD going out. I connected the HDD to another computer and the computer doesn't recognze it. I looked under the HDD on the breadboard and it looks like some there was something that burned out but I never smelled anything and the HDD did work for quite some time before going out.

The HDD is a Seagate manufactired Nov 2008. Maybe it was just old. It seems obvious that the popping sound and HDD failing are related but perhaps the components on the HDD were stressed out due to the power surge but the SSD on the same cable is fine. Any suggestions? I'm typing this message on that same computer. So far, it runs fine but should I return the PSU?


Mar 14, 2020
Buying a used PSU, not to mention repaired one is always a bad idea. Loud pop on when you plug the PSU in the outlet is kinda normal, capacitors are pulling a good amount of current and there may be a spark between PSU and cable leads when you plug it. But a pop when you've already plugged the PSU in and then starting a PC is not normal, return it and buy a new PSU. Failing HDD may not may not to be related to this PSU, no way to tell.