Blank screen on a Dell 1100

[kpictjl]

I have installed Ubuntu 9.04 on a Dell 1100 laptop. The install seemed to go fine. The problem is that when I should be seeing GDM, I see nothing. The screen is on, but I see nothing. I can type in my username/pwd and hear it login, but I still don't see anything. About once every half dozen reboots then I see GDM just fine, go figure.

Any ideas on what could go hosing up the display? Thank you.