sleepless vista troubledshooter

help please...
can't figure how to put a computer to sleep as the message, "ide channel device is preventing this computer from going into hibernate comes up." i have deleted all ide channel devices from device manager and this time, it says, ata channel device is preventing the computer from going to hibernate..

tried looking for answers in the net but so far, got nothing as yet..

i'm not really that good with computers so someone out there help me out please... be detailed please as i need all the help i can when it comes to computers..

by the way, the the os is vista..

thanks so much...