Need help with troubleshooting an odd issue.

[Xiee]

I built a PC for a friend back in July 2020. Before I continue, here are specs:

Mboard; MSI B450I GAMING PLUS AC
CPU: Ryzen 5 - 3500X (with Wraith Prism Cooler)

RAM: 16GB 3200mhz Patriot Viper

GPU: Asus Aero 1650 Super

SSD: Adata 256mb NVME 

HDD: Seagate Baracuda 7200rpm
Case Cougar QBX

PSU: Coolermaster 550w Bronze (Modular)

He uses this PC mostly for work (excel, websites) and some light gaming (Genshin Impact, Dota 2, Among Us). I built him an ITX system because he had very little space at his apartment.

 

The PC was working fine when just yesterday, he claims that the PC won't turn on. So I go have a visit and did some troubleshooting like checking all the wires inside, checking if it was overheating, or if something was causing some grounding maybe. I take it apart the first time clean it up, reseat the RAM and GPU, and try to do some proper cable management.

After putting it back together, it boots and he can do work and game. I stay around for a while to monitor the temps and he's staying around 42-45 degrees centigrade on idle. He turns off the PC while we have dinner at his place. After dinner, when he tries to turn it on again. nothing. No lights, no post. So here I am, trying to figure out what the hell is going on. After taking out the top and checking the cables again and putting it back together, it turns back on like nothing happened. He's able to game normal for an hour or so.

However, when he turns it off again, the damn thing won't turn on! So I go in and remove the covers and the plug and check the cables in the PSU and after I put it back together, it turns back on! It just won't turn on again after he shuts down windows.

Anyone have any idea on what might be happening here? I'm kind of stumped about this. Thanks in advance!

[SupaKomputa]

Maybe the pc was not cleanly shutdown.

Next time it happens, flick the psu switch to completely drain the power.

[Xiee]

21 minutes ago, SupaKomputa said:

Maybe the pc was not cleanly shutdown.

Next time it happens, flick the psu switch to completely drain the power.

Yeah already did that multiple times as well draining the power. Yet this happens everytime the PC is shutdown properly. Thanks for the advice though.

[SupaKomputa]

Swap your PSU with him, see if he got it again.

Narrow down the problems till you can find it and RMA the parts.