Question PC randomly freezes then restarts after a few seconds. Help appreciated. Details in post.

wrathofliom63

Honorable
Aug 5, 2018
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1
10,545
Hello everyone,
I have this pc which has been acting up. specs:

It's a prebuilt (HP Compaq 8200 Elite CMT) with GPU as an expansion card.

GPU: MSI Geforce GTX 1050Ti OC Edition
CPU: Intel Core i5-2400 @ 3.10GHz
RAM: 8GB (two sticks of 4GB)
OS: Windows 10 Home 64 bit
PSU: HP Stock PSU 320Watts
Storage: 120GB SSD (Windows Drive), 500GB HDD, 600GB HDD

Now, getting towards the issue. I'm having random freezes right after which my PC starts. I don't know why, but I FEEL like I can see my screen SLIGHTLY flickering when it freezes. Beyond that, I also feel like I CAN see it VERY SLIGHTLY FLICKERING even when it's working properly. Can this be a gpu or psu issue if its flickering (extremely near unnoticeable)?
After the pc freezes and restarts, it works normally. These freezes are random, and I haven't been able to recreate or get it to freeze again. honestly if I could my life would be easier.

What I've tried is running 3 passes of MemTest86 which returned with no errors.
I've reinstalled Windows, pure clean install with all drives formatted and cleaned.
I've checked temperatures. my GPU hits 80°C under 100% Load, I noticed that was higher than a few months ago and I haven't changed its thermal paste in awhile. I will do it once I recieve it (I've ordered it)
CPU hits 75°C (usually lesser) under full load.
I've tried using DDU.
I feel like I'm at a dead end. I've checked Windows event logs and found nothing there, except this error that goes along the lines of
*"volmgr: Dump file creation failed due to error".*

this initially and still makes me think my ram is dying.
anyway, what do you guys think? is and can this be the PSU? I've had this prebuilt since 7 years. though the gpu is newer. everything else is old.

Additional info:
Before I reinstalled windows, I randomly started getting a new BSOD error VIDEO_TDR_ERROR relating to "nvlddmkm.sys".
I found out I had two of nvlddmkm.sys files even though I'm supposed to have one, so I used DDU. I never got the blue screen again, that fixed it, but the freezing and restarting problem remained.
The SSD is SAMSUNG EVO, But, where I live there's alot of scams and I fell victim. Apparently it's not original but it's a Chinese "mastercopy". Surprisingly it's speeds and performance matched the original and I didn't want to go through the headache of doing something about the scam, so I kept it. I haven't tried to see if it's the cause yet, but can it?

Help is greatly appreciated.