Monitor not going into sleep mode

[JT]

I've been having this problem for a long time. My monitor will not go into
sleep or idle mode. Sometimes it will, but it seems lately, that it won't.
I have updated the video driver per Dell support as I have a Dell Dimension
9100. It worked the day I installed the updated driver but then the
following day, it stopped working. Does anyone have a clue on how to fix
this? I'm to the point that when I'm away from my computer I just turn off
the monitor manually.

 

[Unknown]

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