LeadTek NVS 285 PCI-e under WinXP

I am driving dual-head displays to Orion MPDP panels in a two wide x
one high arrangement. The native resolution of each is 853x480, giving
a combined desktop of 1706x480.

All good, most of the time. However, adding remote desktop just now
broke the multiview settings.

Now, when I reboot I get a message: "A configuration error was detected
on startup! The error has been fixed but it is recommended that you
restart your computer as erroneous display modes can be exported. Click
OK to restart your computer."

An 'OK' restarts, but the error warning persists.
If I 'cancel', and try to change the settings, the "resolution per
display" slider is set to "640 by 150". Clicking on it does nothing but
change the setting label to "0 by 0".

Any ideas on what went wrong? Also, where should I look to decode the
peculiar registy settings that this has left me with?

I am off to do a VGA mode restart, remove hardware and re-install the
driver. A bit messy.

Sounds a bit like XP has no idea what an Orion MPDP panel is and cannot
configure resolution properly. Have you installed custom monitor files?