On Sun, 16 Apr 2017 10:48:44 -0000 (UTC), Diesel wrote:

When you say powered off until you get to the login prompt, Do you mean
you can't have the monitor on to see post status? Does the monitor
remain black during post as well? If not, you might actually have a
driver issue with your video card.

I did restore from an image backup and the problem persisted.

The POST (BIOS) screen (and safe mode and the Windows 'splash' screen)
display okay. But very soon after that, windows does some sort of query or
scan rate setting that makes it go black. (Also, the LED behind the power
button starts flashing.)

If I set the scan rate to 75Hz, it will similarly fail (75Hz used to work
before the problem manifested itself.) So I just set it at 1280x1024 60Hz,
and leave it powered off until I hear the login chime. I used "safe mode"
and gradually increased settings until I found what works.

I don't know why 'switch user' and 'log off' cause the black screen,
because Windows should not change video settings for these fucntions. When
I first had the problem, I was able to power of the monitor before either
and wait until I was sure that the login screen was displayed, but after a
few months this no longer works and I now need to reboot to switch users.


Is your system even worse?

It is a Compaq 7700 (Intel Q965 chipset) and the monitor is a Viewsonic
VA903. (4x3 aspect ratio 1280x1024 max).

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