Mag monitor problems... need help

Your monitor may be dying.

A guess and a test:
When you are opening explorer or some other program
you suddenly display a bunch of white on the screen
which causes a surge of power to the flyout transformer.
In this and some other components this surge causes the
monitor to shut off (although power light is still on).

Test this way:
Do not open maximized windows for IE, Mozilla, or Explorer.
Open them 3/4 or 1/2 size.
See if that causes the shut-off.
If not, then this is the problem.
. . . and your monitor on its way out.

CRT monitors have several components which
deteriorate over time - and then die.

Also, it is probably temperature sensitive.
Hot - it will shut off.
Cool - it will not shut off

If the test above works, plan on a new monitor.
Could last weeks or months . . . or days.

You can also turn down the brightness and/or
the contrast. Both affect the power surge which
come from a full page of white.

You may be able just turn down the brightness
and stop the problem (for now).

Please post the results of your tests here.
Good luck.