I got by fine on my old system: 200Mhz MMX pentium with 96mb of Ram (not PC-100, but EDO). I've upgraded recently though. I had trouble only in keeping it in full textured mode as I moved stuff around. I had to work in the 'box-on-change' mode. Now on my AMD K7 500Mhz w/256 PC133 Ram I can go full textured all the time and move around as fast as I click and drag.

Truth has no value without backing by unfounded belief.
Renderosity Gallery