External portable HDD not working?

[HP2256]

I had an old dell lappy which stopped working so I took the 120GB Toshiba hdd out and made it into a portable hdd now it was working fine and still does but in my pc which has Windows Vista and a 400W PSU it seems that its not getting power since i cant hear the spin but a click click noise but in my laptop which is much weaker but has win 7 it works very smoothly, whats the issue in my PC? Also theres a tick tick sound when i plug usb in back usb panel but absolutely nothing except the led on front panel how is this possible? My usb slots are in working condition as i tested them with my usb cord and android phone but why not my hdd? I also checked usb root hub properties and unchecked "Allow the computer to turn off this device to save power. It doesnt show up in Computer>manage either as I cannot hear it spin but works fine in my laptop

 

[USAFRet]

"but"........ ?

 

[HP2256]

"but"........ ?

sorry clicked submit by mistake