I hav one time typed in hdd password from bios,and know i dont remember it.I can not formatt the disk for new installation of xp,how can i remove the password from the disk,i`v tried it on other laptop and the password still comes up.There are no operating system on it,that is broken.its a Hitachi SATA 160GB disk,that belongs to my acer aspire one,D150 model,give me some hope

If you still haven't resolved this yet, try using a program like "kill disk" to completely wipe the hard drive.
http://www.killdisk.com/downloadfree.htm

Sorry no one got back to you sooner.