If neither his HDD nor his CDROM is showing up, I would suggest that his IDE controller is having problems. Reinstalling the drivers could solve the problem, download them from here:
ftp://ftp.asus.com/pub/asus/mb/sock7...-v/side121.zip
Unzip them, and go into device manager. Look under Hard Disk Controllers. Yours should say something like SIS 5598 IDE Controller. It could possibly say "standard IDE controller". Open it and click on "update driver" and point it to wherever you unzipped the one you just downloaded.