It runs very good on my P4 2.0Ghz (2GB RAM). It also runs acceptably on my AMD K6-2 500Mhz (768MB RAM), although now that I'm used to a 2Ghz machine, it's painful to run it on that one. Run it with Windows 2000, 98 if you have no other choice. 2k is far more efficient and fast. WinME - run away from it. XP - dunno, I refuse to install XP, so I can't offer any opinions on it.