Heres my system's specs:

P4 3.0E w/HT

1.5Gb RAM

ATI 9600xt

19" screen

Right now Im able to run 3 accounts on this computer, without lag. It chokes a bit when I run into a major city, and will give some crazy video effects, but Ive been doing okay to avoid going into the city when I can. Whats the slowest system you've multi-boxed on, what are the specs and how many accounts?