Question Computer Restarts when graphics card is under load

[MoSSi__]

The last week or so i have been experiencing an issue where my computer will restart when the GPU is under load, e.g. playing certain GPU intensive games like squad and escape from tarkov (playing less GPU intensive games like counter strike and rainbow six siege creates no issue and i can play them fine) and stress tests or benchmarks like Kombustor. I started troubleshooting by stress testing my ram and CPU, in which i experienced no issues and also started windows in safe mode to rule out software, installed the latest drivers, checked temperatures( gpu at 65 degrees Celsius and cpu at 55 degrees celsius when playing sqaud) and then i stress tested the GPU with kombustor and my screen went black.i managed to get kombustor to run by undervolting the cpu which was very odd and this leads me to believe its the 500 watt EVGA power supply i've had for only 2 years. however as im not an expert i would like some outside opinion and help from you guys that would help me professionally diagnose this problem or otherwise im just taking a guess at it being my power supply and cant afford to buy another one only to find it wasnt the issue
my main components are:
ryzen 2600x
asus rog strix b-450f
Rtx 2060
16gb ram 3200mhz
nothing is overclocked, all at base speeds

 

[MoSSi__]

also just lowered the power limit on my graphics card to %73.5 from %100 and clocked my cpu back up and kombustor ran absolutely fine, further making me think this is to do with my power supply.

 

[ex_bubblehead]

The initial report of "restarting under load" is more than just a hint at the power supply. Do not go cheap on power supplies, they are the heart of every system.

 

[MoSSi__]

not exactly cheap but thanks for your help,