@AR0x7e7
Deleted my answer after I reread your original Post.
You mentioned you still have problems with just one Monitor installed. I didn't see that or skipped over it.
Then your problem is something else than what I stated in my previous reply.
I would check your PSU to make sure it is working correctly and giving out proper PSU Outputs. You can use OCCT to check that out. Observe all Temperatures and PSU Outputs during the testing if you use OCCT.
All of your PSU Outputs should be within a +/- 5% range for the 12.0/5.0/3.3 Vdc under heavy loads.
as an example your 12.0 Vdc should be a minimum of 11.4 Vdc or higher during idle or heavy loads.
also having 2 monitors connected requires more power and with a failing PSU can cause power issues to occur.
Since you need to physically turn off and then on the PSU to boot up again after crashing.
Overheating APU doesn't seem to be a factor since it is way below the Maximum Operating Temperature while playing games. But possibly something else is overheating.
Also could be a defective APU. I would ask AMD Support - Warranty and see if they believe your APU might be defective or needs to be RMAed to be checked from here: https://www.amd.com/en/support/contact-email-form
Could also be a defective Motherboard so I would also open a Gigabyte Support ticket.
NOTE: Sorry about misleading you down the wrong path. I misread your original post. my fault.
