Weird... Dell monitor stuck in "Power Save Mode"

Hi all. I've encountered a strange problem with a 17" Dell E177FP at work. This monitor was hooked up to a coworker's computer, and one day it decided to stop working. The screen was black and nothing would bring it to life. I.T. ordered a new monitor for him, and all is working fine.

Since I have a video card capable of dual display, I thought I would see if I could figure out the problem, and get a "free" second monitor. I.T. had left it in his office, so I asked him if I could try.

I had high hopes when I fired it up as the lone, primary display. It displays the self test before hooking up the VGA cable. Then, while booting up, I can see the Dell POST screen, and the Windows Logo. As soon as the logo disappears, and there should be the login screen, the screen goes blank, and the power button turns from green to amber. If I press any of the three buttons on the monitor, it displays the message, "In Power Save Mode. Press computer power button or any key on keyboard or move mouse". Of course, doing any of those things doesn't bring the display to life.

If I shut down, and hook up my old monitor again (same model E177FP), all works fine.

If I keep my old monitor as the primary, and hook up the "broken" monitor as the second, I can get into windows fine, and I can even turn on the multi display settings in the nVidia settings, but the second monitor still stays blank, and pushing any button on the face gives the same message. My computer can "see" that there are two monitors hooked up, and I can move my cursor off screen where a second monitor should be.

So, it seems the MONITOR is stuck in this "power save mode" and NOT the computer.

Sorry for the length, I just wanted to point out those things that I have already tried. The most relevant info I can find on a google search is messing with the power save mode in windows - control panel - power options. Changing any settings there don't fix the issue either. Oh, and this is on an Optiplex GX620 with Windows XP Pro. The video card is an XFX 8400GS.

Any ideas out there?