Hi, I’ve been having a really weird issue with my PC and I’m trying to figure out what’s going on.

Specs:

- Ryzen 5 5500

- RTX 5060

- Gigabyte B450M Gaming motherboard

- 16GB RAM (2x8GB 2666MHz)

- Deepcool PF650 PSU

The problem:

A few weeks ago I started getting crashes while gaming. Sometimes the PC would freeze completely with a buzzing “looping” sound, and other times it would just restart randomly.

I tried a lot of things:

- Reinstalled GPU drivers (clean install)

- Reinstalled Windows completely

- Checked temps (they were fine)

- Tried different GPU power cables

- Checked BIOS settings

Nothing really fixed it.

Then it got worse:

At some point, the PC stopped turning on at all.

- Pressing the power button did nothing

- Shorting the power pins with a screwdriver also did nothing

- BUT USB devices (keyboard/dongle) still had power

I thought it was the PSU, so I tested with another one, but the same thing happened.

Weird part:

After leaving it unplugged for a while, the PC suddenly powered on again “by itself” (I didn’t change anything).

Now it works… but I don’t trust it at all.

Extra detail:

- I previously had to reseat the RAM and that temporarily fixed some freezes

- The motherboard and RAM are the oldest parts (around 4 years old)

- The issue seems very inconsistent (sometimes works, sometimes completely dead)

My question:

Does this sound like a failing motherboard?

Or could it still be something else like RAM or PSU?

At this point I’m leaning towards the motherboard, but I’d like to hear other opinions before replacing it.

Thanks!