Old Gateway Computer, no screen suddenly

Hi all, I installed XP on an old gateway a little while ago, and now I'm having some problems with it. Mmk, here's the run down...

Gateway 4000274 Anigma Pentium II Mobo
XP SP1
Intel Celeron
(if you need anymore specs just ask)

Alright, so our main computer was in some trouble earlier, so I had brought the gateway out into the living room where I could use it for internet access to fix the other computer. Later I got the other computer working, and never moved the gateway back into the other room. So, it sat here not plugged into a power source for at least a week (probably more). Then I brought back into the room, tried to set it up, and nothing was coming up on the monitor. I've had this problem before, I switched the power outlet, and that used to fix the problem, so I tried that again, no go. Then I tried a different monitor, and a different cable, still nothing. Tried a different power source, etc. Basically, it definitely is the computer.

So, my question to you is, how do I get the screen back? I've been researching forums, I could unlug the battery in it (not sure how to), something about "jumping" it, a CMOS, etc. Possibly a video card driver, however, as I said before the computer was working fine, the only thing that has changed in the computer is that it has not been plugged in for a long period of time. So I don't think it's a driver.

ALSO, I did get it to work for about 30 seconds. It apparently was a fluke. I got the Gateway screen "Legacy mouse detected..." it was going through that beginning check, and it froze.

If you need any more info just ask, thanks for the help!

The only thing that comes to mind applies if the mobo has integrated graphics. Periodically my mobo flips to choosing a non-existing graphics card. Using the jumper to reset the mobo is the easiest solution. Since then, in order to fly blind, I wrote down the key strokes to manually change the setting. After that it sounds like the graphic hardware.

Ok, how exactly do I reset the mobo? and will this wipe it?

If you have a spare pci video card, this is another option. If the mobo flipped or if the integrated agp video went bad, then you have something to view.

From Gateway:
Picture of mobo location for j24 to reset cmos
http://support.gateway.com/s/MOTHERBD/ANIGMA/m00274/m0027426.shtml

Global view of mobo:
http://support.gateway.com/s/MOTHERBD/ANIGMA/m00274/m0027450.shtml


description of bios setting for onboard video; lacks details for the exact number of key stokes to move to the intended selection. It does describe the correct pci slot for the video card.

http://support.gateway.com/s/MOTHERBD/ANIGMA/m00274/4000274faq6.shtml


Using j24 to reset the cmos loads default values for operation of the mobo. I did not find any user guide for this mobo. FAQs at this site hold some glimpses of the concepts.