blank screen in gnome, works in kde and fluxbox

[starcycle at gmail.com]

not sure what the problem is. i can hear gnome loading, the monitor
light stays on, and i see all the gnome stuff in ps ax. but the screen
just stays blank when it switches from the gdmgreeter. i tried fluxbox
and kde, and those work fine. i have a radeon 8500LE (R200) and i'm
using the xorg radeon driver "ati." i also tried the vesa driver, both
at multiple "safe" resolutions. anyone know what's wrong?  this is
FC5, btw.

thanks,
s.c.