I am trying to install a hewlitt packard 630c drive into a 1.9 ghz pentium 4 machine with windows xp. The device shows up in the bios and the device manager; but when i try and install the firmware update from the hp site it says that there are no recognizable hp drives on this computer.

There is also a second drive on the computer experiencing similar problems, it is a samsung cd-rom sc-148-f. Both drives are not recognized under my computer but can be accessed from the device manager.

can you be more specific on the type of computer said drives are being installed on? a word of advice: hp=oem=trouble. your firmware upgrades were probably written oem-style and may not work for apparently no reason at all.

W2k & XP can have issues recognizing different Rom's .If your bios recognizes the drives correctly and you have confirmed Master/Slave configuration.
I would first Uninstall these drives in device manager and reboot .This will force Windows to re-install the drives. Then try your Firmware update.
Just a note if you are using Nero or other authoring type software , Make sure you turn off Windows writing software.Also make sure you do not have conflicts with these programs if more than one is installed.Nero has a program Infotool, confirm that your drives are recognized in the software