Question Multilevel problems: PC turned off, undetected hard disk, no signal to monitor

May 1, 2020
Here's a puzzler and also my first post here. I'm guessing I know the next step, but I thought I'd also try to get some input from you.

1. My PC had been turning itself off when I played games while having another video/music running in the background. Went on for some month. Temperature was always normal. Now that I had the time, I opened it up to clear up the dust. This had worked in the past.

2. Upon reassembly, it wouldn't recognise the hard disk, but the hard disk was running.
2a. Tried a brand new SATA cable, didn't work.
2b. Tried another plug from the PSU, nothing changed.
2c. Unplugged the SATA cable from the DVD slot (because BIOS recognised the DVD and all USB slots just fine), plugged this into the hard disk. PROBLEM SOLVED, although I've lost DVD access. Bonus solution, the hard disk was only recognised if it ran upside-down.

3. Ran a system check for Windows, PC suddenly turned itself off again. I unplugged every connection from the motherboard, including the PSU plug, visually checked for damage, saw no irregularity.

4. Now my monitor is not getting a signal. Video card seems to be running okay. My guess is that my motherboard has aged and that was where the problems were all along. Because it didn't recognise the hard disk, and now I guess it's not properly allowing an output signal from the video card. Will now perform a POST test.

What's your take on it? Any other ideas?

System: Motherboard: MSI 870A-G54 Video card: RadeonHD 6850 Hard disk: Seagate Barracuda 7200.12


You did not list your power supply brand and model, outside of a failed video card that is the second most likely thing to cause crashing issues. Did you try another video card? Does not sound like you did much hardware testing aside from cables.