Hard drive failing to allow machine to boot

Hello,

i was trying to install an XP on my friends desktop machine . He bought a new harddrive and wanted me to install it. i checked in BIOS to see if the primary and secondary master were set at Auto. i inserted the hard drive but still it could not be detected. I took my own harddrive on my machine which was already working but again it could not be detected. i started thinking its the mobo and i removed the ram i listened to the beeps , to me it seemed the mobo is working fine . when i tried to return the hard drive to my machine it failed again like i have copied a virus or so. The power supply is not turing but if i remove it its working fine but displaying insert bootable drive.

I m really stuck i need help please

thanks