While working on my computer my monitor is going to sleep while lights are blinking on my CPU

Sawyer88

Honorable
Jan 30, 2014
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10,510
While working on my computer my monitor is going to sleep while CPU has blinking lights, i already restarted the machine in safe mode and done system restore but nothing helped.
Sometime after a restart it works for 15 minutes, sometime for 1 hour and sometime only for 5 minutes. What could be the possible reason behind this?
Need Help.