Dell t3500 Display Renders No Signal and USB Pheripherals Not Working. Is the motherboard dead?

Specs: Dell t3500(not mine), Nvidia Quadro FX 1800, 4G of RAM

One of my neighbors told me to fix this pc because it did not work. He has important files on the hard drive, so he offered me $200 to fix it. I took it in and immediately tried to power it on. I was greeted with POST beeps. The sequence told me it was the ram, so I reseated them and the beeps stopped. But upon plugging in the DVI, there is no signal entirely. Also, the mouse and keyboard don't light up except for a split second when they are plugged in. Also tried VGA, HDMI, DisplayPort, different GPUs/graphics cards that I know work to no avail. The front light of the machine is solid green, and the numbers at the bottom are 1-3-4, which has something to do with the 'system board' at dell.com. Monitor isn't faulty because it works on my main setup. Any ideas?