Have you updated your BIOS recently I had the same problem and had to reinstall an older version of the BIOS ie 43 or older to get it working if not use Fdisk etc
I am having problems booting my laptop, it is a HP Pavilion ze4111s laptop, installed with Windows XP Home edition. I have tried using all the system recovery disks that came with the laptop and tried rebooting from the cd-rom but nothing is working. It says eventually when it does something after test bios that HP EEPROM has been reinitialized and to resume or enter setup. when booting from cd-rom and pressing to resume, it says "wrong CD for this notebook".
Any assistance in this matter would be appreciated.