random black screen when leaving the pc for while

[abdo refky]

hi .
when i leave my pc for while , i turn of the monitor .
i come back , open the monitor ,, but i only see black screen .
the monitor is receving signal and the pc is running .
what is that problem .

i have R7 260x
I3 3240
b75m-ds3h

another (( Random )) problem i had before but i think its solved ::
when leaving the PC idle ,, and when i start to use it . i move the mouse and click . the pc restart .
i have closed the auto-sleep , and i think that was the cause of the problem .

any idea ?

 

[emdea22]

Disable sleep, hybernation and don't allow your HDD to shut off. Also set your PC power profile to high performance.