Hi,
For some time it's become a pattern that randomly my screen starts flickering for and I get the beep sound along with the volume display. I should also mention that the beep only comes when my speakers/sound is turned on. Another thing with each flicker the system volume fluctuates by order of 2 values. e.g. With one flicker my system volume shows with 100 and then to 98 and back to 100.
I think it might be a power supply problem so I updated to EVGA 1000W G2 power supply but still the problem persists even though it did remove my HDD loading/reading problem.
My specs are
Intel i7 4770
16GB Corsair Vengeance RAM
4GB Gigbabyte GTX 970
Gigiabyte G1 Sniper B5 Motherboard and i'm using the onboard soundcard.
Here's the screenshot of how my screen looks while flickering and what do I mean by the volume control appearing:
http://i1241.photobucket.com/albums/gg502/dashingboy87/beep_zps9kv9cjtn.png

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