new hard drive

[oldman39+1]

k i installed a new 500 gig hard drive the old 80 gig was full of what lol,. well anyway.. i thought i backed up my old hard drive but i didnt the stuff on old hard drive is still there. what would happen if i pug the old hard drive in while having the new hard drive running??????????????????? would it ask to reboot the 80 gig hard drive ??????????????? just wondering have info on there id like to get ..........