We have found that it is best if that machine is a 486 computer with as few devices as
possible, i.e. no NIC, no sound card, etc. Also it is best if you can use a motherboard that
has only ISA or VESA cards, i.e. no PCI cards. This way when the image is installed on a new
computer, it will easily find all of the necessary drivers as it does an "Add New Hardware".
If the hard drive is from a Pentium, it frequently will have drivers installed for it's
particular primary and secondary IDE controllers, and that may be incompatible with another
Pentium with a slightly different architecture.
But if that is impossible, then in order to make the image easy to install in a wide
range of machines, go into Safe Mode (boot up and immediately press F8),
and select each driver and click remove. If it asks to reboot say no. Continue until
you have removed all devices possible, and then shut the machine down, without
allowing it to reboot (and thus reload all of those drivers).