I have played Linux version of Civilization Call to Power with Pentium 75Mhz with 40 MB Ram with Suse Linux 6 And it wasn't even slow after I replace KDE with Xfwm. And it wasn't even lowest X-window enviroment that I've tested, it was PC with 486/33Mhz with 16 MB and even with that I could read offline html-files with Netscape and it even stops swapping sometimes But I don't think current Linux kernel even fit to 16 MB..