Dell 1850 & RedHat 4: Video Problem

[Shane Presley]

Hello,

Got a Dell 1850, and installed RH 4 on it from CD.  Worked fine, did
multiple reboots.

Then ran an up2date, which included some xorg updates.

After the first reboot the video was still fine.  Second reboot after
the up2date, video is hosed.  The monitor is fine during boot, I see
the graphical RH 4 boot video, but when the logon prompt appears, the
video disappears and the monitor says "Out of range".

The system is up and running, but X is hogging the CPU (99%).  Nothing
in the Xorg logs that looks like an error to me.

system-config-display just hangs (not even sure if I should be using that).

Compared the xorg.conf of this machine to a Dell 2850 which is
up2date, they look identical.  And the 2850, which I think has the
same video card, works fine.

How do I troubleshoot this?

Thanks
Shane