Question Computer keeps crashing

[Salem12]

My PC had been going black screen then just restarting without saying anything. I have an amd gpu so it kept giving me the wattman error , i somehow fixed this issue but i do not remember how since i played with some settings and it just kept working for like months. Now the crashing is back and its worse now ive been crashing and restarting whole doing nothing and i just got the blue screen.
I'm not a PC expert and dont really know too much about it so please ask questions or tell me stuff that i can understand.
I couldnt put my specs on the thread but i will in some time as Im posting this on my phone.

 

[rgd1101]

full system spec? include make and model of the psu

 

[Salem12]

Really sorry for the late post but here is the spec:

Central Processor: AMD FX(tm)-8120 Eight-Core Processor GPU:AMD Radeon (TM) R9 380 Series Video Memory: 4.0 GB Motherboard: Gigabyte Technology Co., Ltd. Motherboard model:990XA-UD3

Total Memory: 8.0 GB
1x external 1TB disk drive 1x fixed 1tb disk drive and 1x 220 gb fixed drive(place where windows is installed)
1920x1080 60hz monitor
PSU:Corsair VS650 80+

ive tried resetting my bios settings or lowering the power drained by the psu and ive tried just lowering every setting in Destiny 2 (it mostly crashes in destiny 2 never crashed while not playing a game)and heat isnt the problem it doesnt go above 70 degrees while playing so i dont know what to do.(tell me if you need more specific info about anything since im not too familiar with the stuff).