Please Help! PC Randomly Reset/Shutdown

[fBlah]

Few months ago my system started randomly restarting and shutting down (cutting off) so I reinstalled windows and everything was fine until a week back, where it started resetting again and more frequently. Sometimes the monitors cut off and pc is running and I have to hard reset. Sometimes it resets on its own. Sometimes it just cuts off. I noticed that some of the SATA ports on my motherboard stopped working and will at times randomly detect/not detect my HDD.

 

It restarts randomly, sometimes when I'm playing games and sometimes when nothing is running at all.

The PC is over 4 years old (GPU 3 years) and I hope its not a motherboard/PSU/GPU issue as warranty has passed.

 

Note that I sometimes run my PC for extended periods of time and it works fine, but it suddenly resets and once it does it resets quite frequently

 

I do not have access to additional GPUs/mobo/CPU/PSU to test.

 

I play overwatch a lot, and I've encountered a reset only once so far.

I develop using unreal engine and have encountered more resets while using it.

 

Things I have done :

Reinstall OS (again)

Run memtest (pass)

Remove overclock

 

System 

Windows 10 Pro 64 Bit

Intel i7 4770k @ stock clocks with corsair h100i

Asrock Extreme 6AC

4x4GB memory

Zotac Nvidia GTX970

120GB SSD Samsung 840 Evo for OS

250GB SSD Samsung 850 Evo for programs

2 TB HDD Seagate ST2000VX003 for data

800w Corsair gs 800

[joshuawi99]

Hmm it could be your PSU. Did you check temperatures?

[Xander Cousins]

Explain, Does any windows sound prompt you when this happens for when you're monitors go black screen? Does cycle like shut down then reboot on it's own? 

 

If prior one then it would be an issue with your GPU possibly dying but you seem to have to restart which usually wouldn't be needed if a GPU is dying as it will flicker the monitors back to life or artefact them. 

 

If the latter one I would assume you PSU is having problems supplying the power required for your Rig, this could be due to excessive power demand or PSU dying on you, I would assume the latter one as that should really exceed 800w.

[fBlah]

No windows sound prompts play when the screen went black.

The screens have gone black only twice so far. Once when the screen went blank, i had music playing and the audio was looping, so I'm sure the PC crashed then. It just restarts (like pressing the restart button) most of the time. The least frequency between restarts was around 5 mins. It doesn't restart immediately after login.

 

No artefacts on screen and no flickering of any sorts. 

BTW how do I log temperatures? When I see my temperatures on corsair link the cpu is around 39-45 idle and goes to about 65 on load. GPU idle is 50 on idle and 80 on load

 

When I check the wattage power draw on my UPS it rarely exceeds 350 watts. While playing overwatch its around 150 watts.