First, you need to remove the side cover which gives you access to the computer's innards. Put the computer on it's side so that the side with the release button at the top of it is upward. Press the button and lift up the side a bit, then slide it off. The next step is to remove the PCI cards. Remove the screw that holds it in and pull it up and off. Next, you need to remove the speaker because it is in the way. Disconnect the two cables that come from the speaker. Press the two latches that hold the speaker in and pull it up. Now, you are ready for removal! Release the two latches that are holding the drives area in and lift it up and swing it all the way over. Disconnect every cable from the logic board and remove the single screw that holds the logic board in. Slide the power button forward until it won't move. Push the two latches that hold the logic board in, slide it forward, and lift it out.
There are many drive bays in this particular model, but I am only providing instructions for the rear bay which is where the factory installed hard drive is. Remove the side cover as described in the logic board section, Then stand the computer up. Remove the two screws holding the hard drive in. Disconnect the cables from the hard drive. Slide the hard drive and it's carrier out and you are done.
Remove the same side cover that is described in the logic board section, then put the computer so it's standing up again. There is a latch that holds the CD-ROM bezel onto the computer. Release it and take the bezel out. Remove the two screws that hold the metal shield on and then remove the shield. Disconnect the three cables from the back of the CD-ROM drive and slide it forward and remove it.
Follow the same instructions as the CD-ROM drive, but remove the floppy bezel instead of the CD bezel. There is only one floppy cable to remove.
Information provided by Doug Brown.