Green glitches on screen and then PC freezes + gpu fan revving issues. Help!

[next_ngl]

Hello,

My gpu has had revving up and down issues for around a month. With little/no load to the system, the gpu would start going to max RPM to 0 and back again, for around 10-15sec, and then would stabilize. Couldn't find a solution online, Windows is updated and gpu drivers were updated, no gpu over heating. Screenshot example is provided later.

Today, I was playing battlefield 4 when suddenly the screen glitched, 80% of the screen turned green and all audio stopped. This again happened but after just logging into windows. This again happened when I got into Battlefield 4 main menu with a crash error "The Error Message reads: DirectX function "Get DeviceRemovedReason" failed with DXGI_ERROR_DEVICE_HUNG ("The device is hung which is typically caused by issues in the graphics driver or aternatively the application"). GPU: "NVIDIA GeForce GTX 770", Driver: numbers".
The freeze also happened when i was just starting my browser. I rolled back nvidia drivers and reinstalled directx but didn't help.

Example of glitches: https://prnt.sc/20xs2zk . This is a tame example, only MSI afterburner got messed up, but other times the entire screen would turn greenish and then might turn black.

https://prnt.sc/20xs0mc This screenshots shows the gpu's activity and it's revving issues. This is with the gtx770 disabled in BIOS, however the same happens when the 770 is the main graphics unit. Not sure what those activity spikes are and why the fans lose control during them, even though the temperatures are safe. Another thing is that the GPU FAN% stays at 33% while the RPMs oscillate. The shapes of the gpu usage and fans' rpm are always the same.

Not sure what's happening. I'll test the gpu with a friend's PSU to see if the power supply is the issue but im still confused to what's happening and why. Currently I'm using Intel graphics to be able to use my PC.

 

Thank you for your time.