I also tried to build my Amithlon machine out of a Celeron 366 Mhz with SB128 sound and GeForce II MX 400 64 Mb PCI. I'm missing a network card with the rtl8039chipset though ... nevertheless the system works perfect with 384 Mb Fast Ram and 8 Mb Chip Ram. But, from the moment that I start to play a game on an original cd with gfx card support I get problems. It simply won't work. Don't know why. I do need to install MUI but don't think it has got to do with games not working. I know that AGA support is not exactly present so I try only games with RTG ....