20-minute delay prior to screen display
Since 2/18/14 my wife's Gateway Desktop running Vista Home Premium x64 SP2 with all updates suddenly developed a problem which has persisted thru today (3/3/14) in spite of running virus scans, chkdsk, memory and disk diags and a whole bunch of changes to power management changes. There were no programs installed on 2/17 or 2/18 but there may have been a windows update. Nothing out of the ordinary shows up in the event logs.
The system seems to run fine all day (most days) properly going into cpu and monitor sleep mode. It wakes quickly when the mouse is moved or a key is pressed. However at 6 or 7 am tapping on the space bar causes the screen to flash the current window and then go black. No amount of tapping keys wakes the monitor. (I did not try CAD to get to the task monitor). 20-30 minutes later the screen is back to sleep mode (display light is blinking) and pressing the keyboard or moving the mouse wakes the dispay and all is well for the rest of the day (most days).
So, most of the time, this appears to be a night time problem. In addition to several system tasks I wake the computer at 3:50am every morning to run an image backup which completes properly. Every couple of days the problem also occurs durring the day.
I have read most of the threads on this forum related to sleep/wake/death screen issuse but do not see anything identiacal to this issue.
Any suggestions would be welcome.