PC Freezes and must hard restart

[michaelmack1014]

Okay so I have scoured this forum for an answer and i have given up. So now i turn to you fine pc masters for help.
specs:
Amd(tm) fx-8350 8 core processor
ASUS MSA99FX Pro R2.0 MOBO
16 gb ram
SSD
Windows 10
Corsair 550w PSU

Here is my issue. Saturday I set this all up, using my EVGA Geforce GTX 970. Tried to launch fortnite, could get in but PC would freeze. Had to hard restart computer to reset everything. So i did clean installed nvidia drivers, Did not work. So i reinstalled windows, made sure everything was updated. That fixed it. Played all day sunday no issues. Now today, Monday, I go to play fortnite, same issue. I clean installed drivers again, ran msi afterburner and raised fan speeds, etc. Still freezes. Now here is where it gets weird. I got frustrated. Took my 970 out and put my EVGA GTX 570HD in, clean installed those drivers, ran the game and bam no issues. No freezing, everything ran smoothly. Im confused because i ran the 970 with an I3 6100 previously and never had this issue, so I am boggled by this. Please any help would be great. Currently the 570 is in the pc but if needed i can quickly swap the 970 in. Again thank you for any help, Id really like to use my 970 since im sacrificing frames using the 570.

 

[MeanMachine41]

Hi michaelmack1014

IMO it could be the PSU as it is borderline Wattage wise and no indication of it's certification.
FX-8350 needs a good quality and efficient power supply of min 650W with your combination.

There are stress tests you can conduct to put your PSU under load and check important Rail Voltages.