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Recently I had my motherboard burn out on me. Needing the machine for work, I purchased a different motherboard and installed that. Generally a reinstall of windows is good at that point but I am not in a position to do that so I just decided I would live with it for now. When I can log-in, everything works fine, what doesn't is getting to the log-in prompt to begin with.

Basically when I first installed the new mobo, every time I rebooted the machine, I would not get the windows login prompt. One of the monitors would receive a signal but the screen would be black. Moving the mouse would not show the cursor and hitting the up arrow key and typing my password and hitting enter (which will normally log you in without mouse) wouldn't change anything. I would then change the monitor configuration around (2 lcd's and a crt) and reboot and at least one of the monitors would work and display the login prompt. I could then go into display properties and turn on the other monitors. However if I rebooted again, I would get the black screen on one monitor again. I would then have to change the configuration again to one not used before and I could re-do the manual setup at that point. I think windows saves the configurations so I had to keep giving it new ones.

Needless to say I've been trying to not turn off my machine. Early this week I actually got the prompt to come up without playing musical monitors. Thinking everything was getting better, I found no harm in rebooting to install the latest windows updates. Boy was I wrong. Now no matter what I do I can't get a windows log-in prompt to display. I've tried almost every conceivable combination. The new mobo has onboard video so I set that in the bios (yea bios screen always displays fine, its not until windows boots that there is a problem) to be the primary video. Still no luck. I have two other graphics cards in the machine which I'm using. Tried all kinds of configurations between those and on-board but still get this black screen of death. I read somewhere that deleting the video drivers would reset the configurations. I logged into safe mode (which works on one monitor), and uninstalled the display drivers. Still no luck and when I booted back into safe mode, it wanted to install new hardware and the display adapters weren't there as expected.

Anyone have any ideas? A fresh install would be a pain and I might be getting my old board back from RMA soon so not sure I want to go through with that just yet. Only thing I can think of is to continue to try other combinations like physically removing the graphics cards. They are both EVGA 8600 cards and the windows boot screen does display fwiw.

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migrated from Jul 23 '09 at 17:48

This question came from our site for system and network administrators.

Perfect question for - use ewok.adventure for the password. – Kara Marfia Jul 23 '09 at 17:48

The problem is almost certainly a conflict between what Windows EXPECTS, and what is ACTUALLY present, in terms of the display configuration. Unfortunately, as you have experienced, it is very tough to get a new configuration to 'stick' in these circumstances.

I'd recommend the following:

  1. Remove all graphics cards.
  2. Connect one monitor to the onboard video.
  3. Check that the onbaord video is enabled in the BIOS.
  4. Boot Windows.

You should now be able to use 640x480, at least. Install your display drivers for the cards you use, reboot. Makes sure everything still works. Now insert ONE video card and connect the monitor to that, and boot. If that works, add another monitor to that card, and so on and so forth, proceeding until everything works again.

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Have you tried the following:

  • Remove the add-on graphics cards, and boot using on-board graphics card only?
  • Looks like you have 3 monitors, so unplug two of them and use only one. Do you get the login prompt now?
  • If either of the above two works (and you can login), try re-installing the chipset drivers for this new motherboard (from the manufacturer's website), and see if you still get these problems with additional monitors.
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Did the old motherboard have onboard video as well? Were you using it, or were all the monitors pluged into the EVGA8600s (newegg's website implies that they have dual video ports). If so, try disabling the Onboard in BIOS, then pluging the monitors back into the EVGA8600s. This may get back to what Windows expects to see, since you have not reloaded all the drivers for the new MOBO.

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