...me some possible reasons? i want to format my hdd and reinstall windows. whenever i insert the xp cd, it copies the setup files at the begining but as soon as it finishes it, the laptop just turns itself off, it happens everytime.

R u trying to install windows while on battery or mains power?
You will need to be on mains power to install windows.

•May be your laptop are effect with Trojan horse virus. Format your full hard disk.
•May be your main board battery is low. Change it.
•Perhaps your XP CD is damaged. Buy new CD. Then try. If you install your CD several times it could be another reason to Damaged your CD

may be the cd is pirated or the capacity(size) of your computer memory(ram) is not big enough to accept the winxp os . so check the cd pack you will see the specified capacity of memory that can accept the winxp os