iMac - 21.5inch, mid 2010 - screen keeps going blank

[FreddyJ]

This happens about or no reason. I've done most of what I can think off and still happening. Nothing showing up that i can see. Any suggestions? Last about 20 secs then comes back on of it's own accord. Doing it at least 3/4 times per working day. Any suggestions? thx

 

[Fishrrman]

Best suggestion:
After 10 years of service, might be time to start shopping for a replacement...

 

[TwoH]

My first suspicions on something like this would be either an issue with a program you have installed, the backlight for the LCD, or the LED driver board inside the machine.