cpu upgrade trouble?

I want to upgrade my dell inspiron 4000, 700mhz to 1g. After calling dell they said it can be done and my mother board will except it. They offered to sell me a chip, of course it would be to expensive, so I declined. After looking around I got one for free from a friend of mine.
Now my issue is once I drop the chip (using batter only) I can boot to bios , just see if the chip being read. And it is 1g/700mhz, stays on for about 30secs than cuts off. With the AC plugged in it cuts off almost immediately, and the green startup lights just flash.
Is there anything I'm missing cause the dell tech says all i have to do is drop go!
Here is some info on the mobo:
DS/N tw-010197/12800-156 4835
DP/N 010197 C/O TW rev A01
Knew cpu: 7135a522 sl53s
kp 001/256
Hope this helps

 

No, when i opened it up it did'nt have any thermo paste on the old cpu or the heat sink. would the bios settings have anything to do with it? If not i'll get some paste, can you reconmend good paste

 

before I go out to by the paste, why would'nt the orignal (700mhz) 1cpu get hot and cut off

 

it was the missing paste...wow thanks

 

So. Are you up and running?