Gpu making noise while playing.

While playing games I've noticed that my Computer begins to make a squealing noise and the screen begins to have lines cross against it. The moment I alt tab the program the noise and lines stop but resuming the program will bring the problem back. Waiting three to four minutes ,while alt tabed, will let me play for awhile until the noise returns again.

My question is this. Is this my gpu running too hot? I've noticed the temps are around 67-69c ,while playing, and waiting must be cooling it. I'm not sure what exactly the problem could be.



Cpu:AMD Phenom II X4 965

Ram:8.00 GB Dual-Channel DDR3

Mobo:MSI 970A-G46

Gpu: GeForce GTX 560 Ti

Hard Drive: 500g Western Digital WDC


I've also run a stress test and had the sound and screen distortion return. I've also used msi afterburner to set the fan speed to 100% to test if that was the noise, it however is not and runs normally. So I'm completely stumped and have no idea what to do.