Averatec 2300. My Averatec 2300 won't start. Very strange problem. It started a few weeks ago.

Question

My Averatec 2300 won't start. Very strange problem. It started a few weeks ago. It wouldn't start, then the next day it worked fine. Then it wouldn't start again. Then it did. Now it won't start at all. Black screen, power light comes on and shuts down when you hold the power for five seconds as it should. No hard drive or cmos activity. I have multiple batts and power supplies, check the memory and HD. Seems like a motherboard problem but I sure hope not. Any ideas?