[SOLVED] Strange sound from GPU under load. Please help.

[The Tiger]

The GPU is Gigabyte Windforce GTX 960 2GB OC. When I start OCCT, after running for a few minutes in 'Power' mode (where CPU and GPU are both 100% loaded), the GPU starts screeching like this (shown in video). The screech starts intermittently, then turns continuous after a few minutes. Note, this happens after the temperatures max out after 7-8 minutes, not before. The screech does not vary in pitch or amplitude. It's either on or off. See the video. (Digital, not analog )

Surprisingly, this does not happen while playing games. This does not happen as well in OCCT, in CPU only or GPU only modes. In CPU only mode, the CPU is loaded 100%, CPU temperature max out at 80C. In GPU only mode, the GPU is 100% loaded temps max out at ~80C. This screech only happens from GPU when both CPU+GPU are fully loaded for ~10mins and temps of both CPU and GPU reach 80C.

Point to note: While both CPU + GPU are in full load (OCCT's Power mode), the 12V rail drops to 11.3V. The PSU is Antec 550W (VP550). The total system load is ~260W measured from wall socket. So the PSU is under 50% load.

Other specs: i5 3570, Gigabyte p75D3, Corsair 1600 MHz 8GB Vengeance. Everything Stock, no OC, not aftermarket cooler.

I'm inclined to think this is coil whine, but youtube search indicated coil whine is different. It varies in pitch and amplitude. What could be the problem? Please help.

Video:

View: https://youtu.be/Jlndswbc-HI



Voltages:

Wall Socket Load:

 

[vov4ik_il]

PSU coil whine....

 

[Nemesia]

View: https://www.youtube.com/watch?v=5zStma_-UCs

View: https://www.youtube.com/watch?v=f4z5Xw7uFKY

Watch them on youtube since they can't be embedded.

 

[The Tiger]

PSU coil whine....

Thank you for your input. It turned out to be a warning sound from Speaker!

View: https://www.youtube.com/watch?v=5zStma_-UCs

View: https://www.youtube.com/watch?v=f4z5Xw7uFKY

Watch them on youtube since they can't be embedded.

WOW! Thank you so much! You are a genius! You perfectly caught the problem and solved it!

I had this CPU warning at 80C on in the BIOS! Prolly set it since I got the PC and forgot all about it! Now I set the warning at 90C and see it's all perfect and no screech from the GPU, (it was the MB speaker! BIOS warning.)

And the 11.3 V reported is a hoax from the mainboard. Maybe the MOSFETS and coils have worn out and developed internal resistance, and not able to fully maintain 12V inside the mainboard? The PSU is fine, as you can see the output in the multimeter.

View: https://youtu.be/_IjoeZuUKc8

 

[vov4ik_il]

Just Wow