I'm assuming the new HD has an operating system on it.
What system and where did it come from?
Is that HD compatible with the PC?
Have you searched IBM for the error code?
HELP!!! just installed a new samsung 80 gig hdd in my son`s laptop and when i try to boot it it gives the message I9990503 telling me that there is no hdd, but when I go into BIOS it tells me that there is a hdd but the docking port is not connected. I have reseated the hdd but still the same, any ides?