Hey guys, thank you for the help and advise. I think I have solved the issue. My CPU was running at 5.2Mhz for some reason. I knocked it back to 4 and I haven't had a freeze since. Its default is 4.7Mhz so I have no idea how it got to 5.2 because I never knowingly messed with it.
Just goes to show you should check every possibility even if you're certain its not what it turns out to be.
Hey guys,
I have been dealing with computer freezes for about half a year and I have an idea what is causing it. The problem is I don't have any spare parts to test the theory so I need to be sure of the issue before I can get new parts. I believe it is my CPU but I cant entirely rule out everything else. I'd love to get some input or things I can do to find out for sure.
What I have done:
Played a multitude of games including rainbow 6 siege, Xcom2 and MGS5 that didnt used to freeze and now freeze within 20mins.
Completely cleaned out my computer, tidied all the cables and made sure the airflow was fine.
I have run a virus check and nothing has come up.
I have defragged my SSD and SSHD's and nothing.
Performed a memory check which showed no memory issues but when my computer started back up it froze on the desktop.
Performed a 3DMark benchmark "Fire strike" and it froze.
Peformed a Prime95 CPU stress test and only froze when stress testing 4 or more cores. 3 or less and its fine. tested one core at a time and no issues or freezes.
Replaced my power supply to the one listed in my specs.
My Specs
Motherboard: ASUS SABERTOOTH 990FX R2.0
CPU: AMD FX-9590
CPU Cooler: Corsair Hydro Series H75 Performance Liquid CPU Cooler
Memory: 4 Sticks (16GB total) G.Skill Trident X 2400MHz
PSU: EVGA SuperNOVA (850W) G2 Power Supply Unit 80 PLUS Gold
Graphics Card: Palit Nvidia GeForce 780 Ti
SSHD (2x): Seagate (1TB) 3.5 inch Desktop Solid State Hybrid Drive 6Gb/s SATA 64MB (7200rpm) 8GB MLC NAND Flash
SSD(OS only): Kingston SSDNow V300 120GB 2.5 inch SATA 3 Solid State Drive
I'd appretiate any input towards a solution to the problem and if I have missed anything please let me know. Thank you in advance.

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