I have a couple of user's that seem to be having this issue. Both
users are running a Dell Optiplex 745 with a DVI add-on card. They
have a 21" CRT (VGA) as their primary, and a 17" LCD (DVI) as the
secondary. The VGA monitor is plugged into the onboard video, and the
DVI plugged into the add-on card. The problem seems to be when the
machine is in standby mode for a long period of time, the primary
monitor switches to the LCD, and the CRT is detached. This doesn't
happen everynight, but does happen intermittently. I have tried just
about everything I can think of to fix this to no avail. Here is what
I have tried thus far:

- Upgraded video drivers to latest version (Intel Q963\Q965\G965
Graphics Controller v.6.14.10.4704)
- Installed a new PCI-E video card that will support Dual Monitors
and upgraded the drivers for that as well (256MB ATI Radeon X600,
Driver v.8.263.0.0)
- Flashed the BIOS to the most recent version

Any advice on this would be most helpful, as it is quite frustrating.