I have no power. I replaced the power supply, removed all drives, re-seated the memory, replaced the MB battery. No evidence of power to the main board. Am I looking at a bad board? Where can I find a replacement board.

The eMachines computers are well-known for power supply/motherboard issues. I went through the same thing a couple of years ago. It is unclear which goes first, but it usually takes out the other. More info here.

Replacement parts--if available--will be more expensive than just buying a new computer (I'd suggest Dell) and you'll still have eMachines hardware.

Hope this helps,
WallyH

That machine has a Celeron processor. I would not spend a penny to upgrade it. Best Buy has a Compaq machine with an AMD Dual Core processor, 3G of RAM and 320G HD for $369.