So far I've gotten away with a CPU upgrade, hard drive replacement (same make/model), and a video card upgrade. I had to reactivate after reinstalling on the new hard drive (obviously) but not for the other hardware changes.
You must be using the wrong HAL. Windows 2000 handles up to two physical CPUs (cpu sockets). Windows uses the same HAL for multi core and multi cpu systems. Your admins may need to select a "custom" HAL at the time Windows is installed. http://www.microsoft.com/hk/windows2000/faq.htm On topic, Windows 98 isn't going to do to SMP any time soon. It's time to move on to a modern operating system fellas!
I completely disagree with your statements. Adding an additional Vista SKU is a monumentally bad idea. Obviously, Windows is not for you. Have you tried Linux? Windows 2000?