OK. I copied an xorg.conf that I know works for the machine into /etc/X11 and tried both "startx" and "sudo startx". No joy.
I dropped into root (sudo su) and ran Xorg -configure. That failed.
I also tried installing graphics-2.6.29.1-tinycore.tcz. That also failed.
Installing the full xorg also failed. I'll continue to experiment and report back if I can find an xorg.config that works.
It looks like xvesa may be the best option for the Eee 900. That's really no problem for me since I generally prefer xvesa. DPMS support, however, seems necessary in order to have support for standby. . . . Unless I can figure out a way to switch off the lcd backlight when "echo standby > /sys/power/state" drops me into a terminal screen. If I could do that, then I think the computer running xvesa would go into true standby mode. That would involve some direct harware control software.