Hard drive wont boot

I attempted to repair xp home edition on a friends computer (e machines t2542) he didnt have any disks so i used my copy of xp sp3. first thing i tried to boot with it to no avail, it would start setup then the computer would turn off by it self,so my dumb butt does it in windows it worked yea! so i thought upon restart windows said i had to activate but when i clicked yes it did nothing after many differnt attempts,i gave up and got the computer to go into safe mode from there i did a fresh install on a 2nd hard drive i put in it,so i had 2 versions of windows on the computer from the slave drive i used swissnife to format the primary drive and thought i had the slave now set to primary but nooooo.i restarted computer and now it says no operating system,and if i change the cables making the slave drive primary it says ntldr press any key to restart,ive tried a couple differnt boot disks and if i try to change any parameters for the hard drives or mainboard the computer turns it self off. guess its self aware of my peddling, im lost i dont know what to do if i could get around it being aware of what im doing i might be able to fix it