compaq m2000 won't power up

This compaq M2000 was my sons and one day it stop powering up. with the help of this forum I took this machine apart and replaced the processor and heat sink from a V2000 I was given for parts. Can't tell you how wonderful it was when this M2000 powered up perfect and worked like a new machine.
after 5 or 6 hours I shut down this machine, that later I tried to power it up with the charged battery. It lite up the power bar that went dead and we are back to square one. dose anyone have a suggestion that might help me? thanks for your replys Bixxl

 

could you put a link to the thread where you got guidance in how to replace the CPU.

I think the CPU was fine because I've seen a lot of faulty laptops and the CPU was never at fault

 

Try taking out the battery pack and AC power

Hold the power button for 30 seconds

Then turn it back on with only AC power

 

Hi Nation and Flipfire
I tried your suggestion Flipfire and still doa.
Nation I guess I wasn't clear on the Info about changing the CPU. The info from the sight was how to remove the back of the computer, the rest was easy.
I don't think it was the cpu unit ether, my parts machine powered up with the CPU I took out.
The m2000 that is doa has been for a year or two 4 months ago of a fluke I took the machine out of my closet and pluged it in and it powered up for about half an hour than a little pop and doa. Can you give me some pointers on where to go now?
thanks for your help.

 

Try reseating all memory, cards and cables. If you have more than one memory stick, try booting with only one installed, then try with the other if the first didn't work.