laptop help please!

[Eppidrummer]

I have an hp pavilion N5430 laptop. I bought it as is because it would not power on. Here is the deal; The power button came on for about 3 sec then shut off. And thats it. So I removed the Duron cpu and replaced with an athlon. Then the power light came on and fan started. The fan ran for about 3 sec then shuts off but the light stays on. I then swithched back to the Duron cpu and now the same, light and fan starts, fan shuts off in 3 sec, light stays on. No screen or anything else seems to run. Also, the battery is dead and will not take a charge. Thanks for any advice.
Eppimail@sssnet.com

[pelicanman]

If it's shutting down that quickly it's likely that either the memory is bad (try swapping) or a system board component or connection is defective. If memory swap doesn't work you're probably going to need a new motherboard.