I built up this PC for almost 4 months, never has any issue until recently.
At first, about 1 weeks ago, it took sometime(at least 30 minutes to an hour) before black screen occurred while playing Diablo 3.
Now, it happens quite fast, just entered game for not long (as in video), and issue occurred.
While I also tested Dota 2, it will takes more than 20 minutes before same issue happens.

Mobo: Gigabyte H370M D3H
CPU: Intel i5 9400F
GPU: Galax RTX2060
RAM: 1 x 8GB, 2 x 4GB (All DDR4)
PSU: CoolerMaster 650W

What I observed:-
1) Black screen (No signal from GPU). Turn on and off still same.
2) GPU fan speed spin at full speed
3) Game sound continue playing. As for Dota 2, I still can hear all the sound(not only music) continue playing after 2 minutes, means PC was not totally dead that time.
4) Hard reset, mobo beeps for 5 short beeps, not booting up.
5) Hard turn OFF and ON, PC boot up normally.

Did you check your temps after u turned on your games?

if that is a permanent setup, there are too many issues with it. please do something about it, it may fix your issues:

1. please get a proper psu. Not only you have an old cheap psu, you use molex to 8 pin to power a 2060. the 2060 may not be getting stable and clean power consistently, that alone will cause it to degrade over time and i won't be surprised if its dying.

2. please attach your drives to their proper mounts/trays. if necessary, get a new case to support your amount of drives. for gods sake, piling two heavy 3.5 hdd on top of an ssd, you think your ssd is a tank is it? also putting all of them on top of the psu, a cheap one some more. i wont be surprised if the heat as well as any possible leakage/interference from your psu spoiled your drives.

Please do your research and learn to build a pc properly, safely and responsibly. You damage your own components because you were too cheap or too lazy and now you expect a miracle if we can help you fix an already broken pc by its own owner.

This post has been edited by thewan: Dec 2 2019, 02:26 AM

Heat is well known killer to electronics goods, yet you sandwich the SSD to 2 sources of it.
Maybe the high temperature make the SSD stall/hang, in long term will spoiled your SSD.

5 beeps = no display card.

So Galax does not have its own driver and relies on Nvidia for drivers huh?

Uninstall Galax monitoring/tuning software.

I would go like this. Download Nvidia WHQL driver not BETA drivers. Install updated drivers. Then try games. If it works, the problem is very likely Galax software.

Cheap skate CPU Cooler with cheapskate Heat sink compound.
If I were you I would change to coolermaster 2XX and use Arctic Silver Heatsink Compound.

Harddisk bracket is not difficult to locate.