Pc shutting down , without overheat

[Nikzja]

My Spec:
GPU: Sapphire rx 5700 xt nitro+ 

CPU: AMD Ryzen 7 2700 
RAM: G.SKILL Trident Z 16GB (2x8GB) DDR4 3200MHz 

PSU: CHIEFTECH 600W 
Aorus b450 elite motherboard 
 

My pc shuts down when I start a game. Well , not every game tho. Recently I tried X.M.P and it was working fine , until I started playing with Cyberpunk , where the problem begin. After like 15-20 min of gameplay in medium-high settings my pc just shuts down without restarting and anything , first i thought my card overheat , but then i checked everything it was on 80celsius ish. I tried to figure out everything , and without X.M.P I barley got 60 fps which is werid , cause when i enable it and my ram runs at 3000mhz I got 90-120 fps. Anyway, I just ended up not playing the game , and turn up my fans on the card , when I was playing other games like AC valhalla , but after 3 hours of gamplay , my pc shut down as well. And it was going on like this , and I ended up just leaving the newer games , and played like Valorant , etc which it cpu heavy game so my pc wont shut down. Today I downloaded Apex Legends , which I played in this congfig like 160 hours without any problem, and as soon as I launch the game , it load up correclty , then I click on anything and my pc shut down instantly , like in the main menu , so it can't overheat , I checked the event log , and it say: event id 41 kernel power , and Im suspecting that the PSU is kinda old like 4 years old at least , it could be broken or will be soon , but I would like some help , maybe I'll got some other answers , that can cause this. Oh and I tried timing the ram properly in the bios and everything , it did the same thing. I have this problem for like 2 months now. 

[puppo]

try to change psu, if the problem persists then try to check if its a cable problem (maybe something not plugged right and some cables damaged)

[Pixelfie]

What specific PSU? Chieftech makes good and bad PSU's. A PSU shouldn't die in 4 years, most will work at least 10 years

[frozensun]

Random reboots are usuall RAM and PSU issues,taking in concern you don't have overheating issues of any component.

Who knows if your MoBo likes your RAM.

Ryzen is very sensitive to different RAM.

These issues need to be solved by a process of elimination not on forum.