|Presumably this is an EIDE system - not SATA drive etc.?|
Also does it use Cable Select (CS) or the older Master/Slave configuration?
Check the (jumper) settings on the "new" drive as well as that for CDROM;to see if they are set correctly.
This post (from 2007) deals with assorted possible solutions:
Also is the XP setup disk a bona-fide one from M$-land, or HP? Or is it a recovery disk - and if so what is its provenance (did you make it way back when)?
Is the CD unit only CD device (not DVD as well), and is the XP disk you have a CD or a DVD? Or is the "CD unit" actually a CD/DVD unit?
message edited by trvlr