Question PC started having issues today at random.

[adampd]

Hi all, my trusty gaming pc suddenly started having what appear to be hardware issues today, out of the blue

I've had it now for about 6 years and it's had infrequent minor upgrades like SSD's etc

Spec is -
GA-X99-SLI
Intel i7-5820k
16gb of Ram
Nvidia GTX 970
Windows 10
Samsung 850 Pro 1tb
Samsung 850 Pro 256gb
Samsung 850 Pro 256gb

The only minor issue/concern i've had up until recently is Windows identifies my 1tb Samsung pro as a 256gb drive, but it's not a fake ssd, as it's over half full and magician says it's genuine.

Today when just casually working and not doing anything intense, the pc just restarted (As if I'd hit a reset button)
It booted up and was a little sluggish for a few minutes, but then worked fine for a few hours
Then about 20 minutes ago, I had a 3d game minimized and a youtube video playing and the monitor went into standby, the music video and game were still running in the background, as I could hear the music from youtube and the background drone in the space game I was playing
I tried alt+tabbing, alt+f4 to try and close apps, but nothing
So I ended up having to hit the power button to soft shut down.
I've just installed the latest nvidia drivers just incase, but i can't think of a reason why it's suddenly acting up.
Any thoughts?

 

[refillable]

No overheating issue? If not you might need to reseat things in place as they might get loose.

Also, what's your PSU?

 

[adampd]

Thanks for getting back to me.

PSU is a Coolermaster 700w Silent Pro.

Temperatures for the CPU under load have always been good, the max they peak at with 100% usage is 58C (51-59 across the cores)
I did a quick OCCT CPU test for 5 minutes and the temps peaked at 59 in total.
GPU without load is around 56c, I haven't yet tested that under load, i'll do that here in a second.

I thought the problem might be a specific new Early access game I'm playing, but it did the same thing when playing Rimworld, then after I rebooted, just before the Windows login box pops up, the screen turned off again.

 

[adampd]

I think the issue might be driver related, as I checked the windows error log and it shows this at the time of the monitor going into standby:

3 entries:

Display driver nvlddmkm stopped responding and has successfully recovered.
Display driver nvlddmkm stopped responding and has successfully recovered.
Display driver failed to start; using Microsoft Basic Display Driver instead. Check Windows Update for a newer display driver.

I did update the nvidia drivers a week ago, maybe slightly less, and used DDU to remove the existing ones.

So I removed the nvidia drivers and let Windows update install drivers instead, just to see what happens, so far, after about an hours use, no crashes.

I ran a quick GPU / PSU test in OCCT and no crash, temps for the GPU were from 55-61C

 

[adampd]

Well, things just went downhill fast. Tried a different driver version, logged into a 3d game, monitor goes off, sound stutters a bit, then nothing.
Turned the PC off, waited 10 seconds, turned it on, still no display.
The PC no longer posts, but does stay on, i tried a different PSU (a much better brand/higher wattage), still nothing.
I moved the gpu into the 2nd PCI E slot, nothing
I removed the card and turned the PC on and the PC actually boots up normally in the background.
So I assume the card has died?