Why does my iMac screen keep switching off / going black?
After about one half hour of use my new iMac screen switches off / goes black.
The screen can be switched on by pressing the power button on the back on the machine a few times. It remains lit for about 20 seconds. This can comntinue for about half an hour when it stops switching off or when I give up.
I have conrtacted Apple but they have been unable to solve the problem.
The machine is just not fit for purpose as I cannot use it for work.
It appears from the internet that this is a recurring imac problem.
Please, what am I to do?
iMac, Mac OS X (10.6.8), Mac OS X 10.6.8 (10K549)