Computer trouble! VGA cable works, DVI-D doesn't (SOLVED)

[Raggit]

***NOTE***
I finally solved this problem by simply running system restore.  I still don't know what caused the problem in the first place, but it's fixed now.  Thanks for your help all!



My Dell Flatscreen monitor has been working great for the past year since I got my new computer.  Then, this evening, I turned my computer on, and it booted up just fine.  Then, where the Windows XP splash screen should be, nothing!  Just blank.  Then my desktop loaded (I could tell because of the sound of a little message popping up in the corner alerting me to update my virus stuff which I uninstalled.  Happens all the time, so I know the desktop loaded.)  Still, the screen was blank.  I used the Windows tab on my keyboard, and hit "U" twice to shut the computer back off.

After some experimenting, I unplugged my DVI-D cable from the computer and monitor and hooked in the VGA cable.  It worked!  However, I want to use my DVI cable, not the VGA. 

Does anybody have any idea why my DVI-D cable stopped working all of a sudden?  How can I get it back to working?  I can use my computer with the VGA, but it's only a temporary fix.  I WANT MY DVI BACK!!!11!1!  :'(

Any help will be appreciated.  (And yes, I've Googled the problem with few results.  It's happened to others, but their solutions don't seem to be working.  One provided a fix by altering the BIOS settings, which I would like to try, but the only menu I know how to access is the boot menu.  Is this the same thing, or is there a specific BIOS menu I'm not knowing how to access?)

[covox]

When you say "booted up just fine", could you see all the BIOS POST messages being output via DVI? Or was it blank from the moment you turned the computer on.

Also is the card NVIDIA or ATI?

[Raggit]

I could see everything just fine prior to the Windows XP startup screen. 

I have an ATI Radeon card. 


I called Dell, and they said that the only menu to access are the startup menus (F2, F11,)

I'm using my VGA cable for now, and I guess it's okay. 

[GarageGothic]

Do you mean the Windows boot menu? If so, that's not the same as the BIOS menu. The BIOS menu is usually accessed right after starting the computer, while the memory is being checked (depending on your motherboard manufacturer, the screen may be covered by a logo graphic while this is going on). If there is on-screen text during the bootup, it usually tells you what key to press (DEL on my computer) to access the BIOS setup.

On this site you can find the right key to press depending on the brand of the BIOS/computer.

[covox]

Right, well your monitor and DVI connector are both fine, as you're getting an initial picture. The problem most likely lies with your graphics driver. Try installing the newest Catalyst driver pack and see if that improves affairs.