I'm using Win2k Server without installing the server apps. It runs on a Cyrix 6x86 pr233 (really 200Mhz, I hate PR ratings) with 64 Megs ram. It runs as fast as NT did on this machine, but when viewing my Task Manager, I can see why I could use another 64 megs of RAM. 64 megs is ok for now; at this moment I'm playing mp3s and surfing, don't notice much more lag than with NT4 or win98, and it's way more stable than either. I wouldn't trade Win2k for anything else MS makes. BTW, I bought win2k pro, but my cd got one tiny scratch, and the install proggie wouldn't load a few files... so I borrowed the W2k Server disk from work. The serial worked and I'm not using any of the server apps, so my conscience is lifted.
Twisted365