Windows Login Screen is Blank/Black/Missing

[Qkix]

I have an old HP Pavillion running WinXP Media Center Edition SP3 with an NVIDIA Geforce 9600GT video card with recent/current drivers.  Sometime between the time I went to bed last night and tried to log in this morning the Windows log-in screen stopped working.  I left an Adobe Acrobat (Reader) document open so that I would see it first thing this morning, (non-administrator account) but that is all.  My anti-virus is set to do its full scans on Monday morning, so it should not have run last night, and the monitor was turned off.

When rebooted the computer appears to boot normally, but when it gets to the point that the login screen should be displayed the screen is black/blank instead.  The monitor indicates that there is a video signal coming from the computer (green power light vice amber), but nothing - not even the mouse cursor - is displayed on the screen.

I am able to boot into safe mode and use the computer that way, which is how I'm posting this.  The video drivers are recent; I normally update them every few months so they should be current if not the absolute latest.  I've played with the video settings in control panel while in safe mode, but it hasn't made any difference.

Any suggestions for fixing this would be appreciated.

[JJ 3000]

Tap the F8 key as the computer is starting up. This will open the advanced startup screen. At that screen choose Last Known Good Configuration.

[Qkix]

Tap the F8 key as the computer is starting up. This will open the advanced startup screen. At that screen choose Last Known Good Configuration.

That's one of the very first things I tried.  No change.

[JJ 3000]

Do a system restore from safe mode.
http://www.computerhope.com/issues/ch000589.htm

[13fontad]

Does a system restore from safe mode help?


Denis

[Qkix]

I tried system restore and was told it failed.  On the next boot I got a message saying that Windows couldn't start because the config.sys file was corrupted or missing.  I did system recovery and had low-rez video with no Nvidia drivers installed.  As soon as I reinstalled the Nvidia drivers, the problem returned.

Thinking that it may be a bad video card I bought a new one; my computer meets the stated system requirements.  Only when I install it, I get zero video - green light on the monitor but absolutely nothing on the screen) and the computer gives one beep every 20-30 seconds.  Put the old card back in because something (video in safe mode) is better than nothing.

Next step I guess it to try swapping monitors.

[Qkix]

I hooked the monitor up to my laptop and it works fine.  The problem is in the computer itself.

[13fontad]

I would say.....


You may have a corrupted driver that may have had a virus on it.



Denis

[Qkix]

I've uninstalled and reinstalled the drivers several times but I'll try running MSE again.

Today I installed yet another new video card and without the drivers it was fine.  With the driver installed I have the same problem; the screen goes black at the Windows login screen and the computer beeps every 20-30 seconds.  I noticed today that if I don't do anything the computer reboots itself after a few minutes.

Could it be the motherboard?  I ran the hardware diagnostics software that came with the computer, PC Doctor I think it is, and everything passes.  But I don't know what else to think.

[Qkix]

Resolution:  Turns out it was the monitor all along.  I installed an old monitor and it worked fine.  For some reason the bad monitor worked with my laptop but not with the PC.