|"i am changing the processor in to pentium centrino"|
Centrino is NOT a processor, it's the name of a specific Intel hardware package. The processor used in the Centrino package is the Pentium M. Which processor are you attempting to install? And which processor did you remove? Hopefully you're not confusing Centrino & Celeron because a Celeron would be a downgrade, not an upgrade. What do you expect to gain by swapping processors anyway? The processor speed varies under load so unless you're really pushing your laptop to it's limit, you'll probably never notice any difference in performance
"Centrino is not a processor. Rather in order for a laptop computer to be called "Centrino", it required the new Pentium M processor, an Intel 855 chipset, and an Intel PRO/Wireless 2100 (802.11b) or Intel PRO/Wireless 2200BG (802.11b/g) network card."