Windows computer black screen after 5 minutes of use, PC still running

[Adam187a]

Hey guys! Recently just decided to build another PC with extra parts I had laying around.
These are the specs:

CPU: AMD A10-7800
RAM: 2x4GB HyperX 2133MHz DDR3
Motherboard: Gigabyte F2A78M-HD2
PSU: Silverstone 500w 80Plus
Stoarge: 250GB HDD (Not sure on exact model)

So my problem is either within the CPU, PSU or the graphics card. I've narrowed it down to these but any normal computer person would blame the graphics card for the issue.
I installed Windows 7, after loading Windows I decided to download the drivers, every time I'd install the CPU drivers for the full APU potential, Windows would always freeze at the boot logo. Every time, if I used last known configuration it'd remove the drivers and I'd be able to use the PC again.
Reading around I came to a conclusion that it was the PSU, so I bought another...

PSU: XFX PRO 550w Core Edition 80 Plus Bronze

Now I installed Windows 10 to get a fresh copy of Windows on there and also eliminate any OS issues, this time, I can use the PC for about 5 - 6 minutes (approximately) before the screen goes blank (black with backlight on) and the computer still running with everything on. Normally when the PC is running the fan is rumbling but when the screen goes black the fan is just a constant hum with no rumbling at all. I still haven't been able to download the APU drivers because of this lol.
Reading around, I came to another conclusion that it was the APU's iGPU failing? So I inserted a...

GPU: MSI Nvidia GTX 650 1GB

-just for the process of elimination. The only difference this made was that the intake fan was on FULL blast about to go home. So now I'm baffled, another dead PSU? Or is the APU just dying? I have an AMD A10-7870k that I could use to eliminate another possible cause...

Note: Used HDMI to HDMI for the iGPU and DVI to DVI for the Nvidia GPU.

I know it's an old system, but it'd be great to know what's causing this problem and if I can come round this? I'm now also quite sure that maybe the HDD is failing but would that really be the cause of the black screen..??

Any replies at ALL would be greatly appreciated

 

[Adam187a]

Update: Just loaded optimised defaults in the BIOS although never touched them, seems like it resolved the error in some way. I now received a blue screen with the error "THEAD_STUCK_IN_DEVICE_DRIVER"

 

[Adam187a]

Nobody knows...??

 

[Alex Fare]

Going through same issue. Noone here seems to know.

 

[Adam187a]

I found out the issue by a process of elimination, no one here knew but at PCPartPicker.com I was actually able to get some replies; unfortunately none of them knew either.

In short, it's the APU. For some reason, the graphics side of things weren't working and would black out the whole screen whilst the monitor and the computer are both powered on. I changed it to an A10-7870k to find this out...