So I've solved the problem after almost two months of trying different things. It was a CPU defect despite I was able to run Prime95 for 2 hours straight without any issues.
For anyone still having the problem, try booting your PC up with only 1 thread first in System Configuration to see if the artifact issue still persists.
Search for "System Configuration", go to "Boot" tab, click on "Advanced options...", check the "Number of Processors" box, and select 1 processor. Then it will prompt you to reboot. After rebooting, check whether the issues have gone away.