Binary package hint: compiz
The ES1000 chipset doesn't support 3D at all. It's found on server mobos, for example. It's not too slow with gnome and firefox, although it (currently?) doesn't support RENDER acceleration.
Anyway, Intrepid Alpha 4 (desktop amd64 and i386) boots up to a light gray screen with only a mouse cursor visible. This only happens after the "ubuntu" user logs in: the gdm screen is fine. I was able to switch to a text console and killall compiz.real, and then I could see the gnome desktop. There didn't seem to be a window manager, but I was able to rectify that by going into properties->appearance and turning compiz on (graying out the screen), then I think blindly clicking effects back to none. I did switch to tty1 and kill compiz.real again, though. So maybe it was just not killing compiz that was the trick. Anyway, ATI ES1000 needs to be blacklisted for compiz.
Xorg.0.log:
...
(II) PCI: 0e:0d:0: chip 1002,515e card 1028,01b3 rev 02 class 03,00,00 hdr 00
...
Probably you should blacklist anything where glxinfo shows:
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.2
...
OpenGL vendor string: Mesa Project
OpenGL renderer string: Software Rasterizer
OpenGL version string: 2.1 Mesa 7.1 rc3
...
Xorg apparently sets up a software direct renderer or something, so looking for direct rendering: Yes no longer tells you whether you have hardware 3D.
Thanks for your report. What does "xdriinfo driver 0" return for your card? I think blacklisting per DRI driver (or lack thereof) in combination with card ID would make sense.