You should run the Dell diagnostics on your graphics adapter. The instructions are in your manual.
I have a Precision 390 and an NVidia Quadro 4500 graphics card, which was recently installed (used to be a 3500) by Dell tech support. Worked great for a week or so and then the monitor stopped working. When I turn on the computer, it boots up normally, all the fans running, I hear the windows startup chime, but the moniter never turns on - it's power light remains amber. If I disconnect it from the computer, then it will turn on (power LED green) and display the "no signal" message. If I plug it back into the computer, it just goes back into standby mode.
I have tested the monitor with other computers; it works fine. I have plugged in other monitors; same problem. I also tried reseating the video card, but that didn't change anything. I tried starting up in safe mode, but the monitor still never comes on. I've contacted tech support again and they're supposed to call me Tuesday, but my warranty only lasts another 11 days, aaaaaaah! I think they're going to replace my motherboard and my video card (again). Any other ideas of what the problem could be?

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