1. Opened the tower and reseated the motherboard and ALL plugs?
2. Removed and reseated the memory modules one at a time?
3. Checked for bulging capacitors that may have caused the motherboard to fail?
4. Removed and reseated all PCI cards?
5. Unplugged all CD & DVD drives, then attempt to start?
Hope this helps.
My 11-year old nephew has a 18-month old emachine t2890 (piece of garbage) and last night he shut down as normal, yet went to restart the system today and it will not start. I checked it out, replaced the power supply yet no action or power. There is a green light on the motherboard but still it will not fire up. Any suggestions?