Problem if no key depressed for 30 mins

[John]

If my PC is left running but no keys touched for about 30 minutes, the
monitor light changes from green to amber as though the system has shut
down. This occurs whether or not my broadband connection remains active.
Although the keyboard light remains green, touching any key fails to bring
the monitor back to life as it used to. I have to press the restart button
on the tower, meaning the PC goes through the whole boot up procedure. Is
there a simple adjustment that can be made to my systems' basic settings?

 

[Shenan Stanley]

If my PC is left running but no keys touched for about 30 minutes, the
monitor light changes from green to amber as though the system has
shut down. This occurs whether or not my broadband connection remains
active. Although the keyboard light remains green, touching any key
fails to bring the monitor back to life as it used to. I have to
press the restart button on the tower, meaning the PC goes through
the whole boot up procedure. Is there a simple adjustment that can be
made to my systems' basic settings?

Turn off your monitor power management in the Display Control Panel -->
Screensaver tab --> Power.. button --> Power Schemes..

Set the monitor to never go off.