does the fan on the backside of the computer turning? Best thing to do is pull the cover off and then power it on..look to see if any of the fans spin. If the fans spin etc. then it's getting power and probably there's another problem.
If there's a switch on the backside make sure it's on. wiggle the power cord. Could be the power supply is dead. I've seen a few e-machines with broken power switches.
Most shops will have a power supply tester or will plug in a good power supply to test your PC. They should be able to tell right away if it's the power supply or motherboard problem.
bobalou, November 2010
