PETEN767 said:
After about 2 hours my monitor shuts off, and will not come back on.
Diagnostics do not show hardware problem
Try another monitor. Your problem might be with the graphics electronics
(maybe a card) in the computer instead of the monitor being at fault. It's
probably the monitor being heat sensitive (bad solder joints due to
expansion and contraction of them due to heating and cooling cycles, common
with CRT type monitors and TV's after about 5 years, although it could be a
bad electronic device that's heat sensitive now). Also, check your power
savings settings on the computer if it only goes off after you've not been
doing anything with the mouse or keyboard for a while. You can check them by
right-clicking your desktop, selecting Properties, then the Screen Saver
tab, and then click the Power button.
