Gateway GT4022 desktop Will not boot.

My uncle came to me with this machine. It will not boot, it wont even post. The fans come on and the HDD led blinks. I opened the case and it feels like the HD is spinning.

Its Blue Led light that says it on is dark and it is not sending anything to the monior. I have tried replacing the video card since I thought the machine was running. Nothing… I have reset and cleared the cmos, (resetting the jumper and removing the battery for 1 minute)

I am hoping its not the MOBO because I dont have the time to hunt for one that will take the legacy ram and processor. So any other ideas I would be very greatful.

Thank you