I’ve been having this problem with my system ever since I added a second monitor. I set up my display settings such that my monitor 2 is my default display and the display is extended to monitor 1 and arrange them how I like them to be. Then I reboot the system at some point later and the monitor configuration is reset. After the system comes back I am back down to just monitor 1 being my only display and I have to re-configure my display settings all over. I’ve tried everything setting up the display settings in ATI’s Catalyst software rather than the native Windows Screen Resolution control panel. I’ve tried removing and re-installing the drivers, why won’t these display settings stick?
In Windows 7 x64 SP1 the order of multiple displays in an Extended monitor setting may be lost or reset after the system is rebooted. After each restart the monitor configuration is reset back to using only a single monitor.
After an extended Google search session, I finally found the fix. It’s a registry key that needs to be cleared. Here’s how to:
[step 1] Open the Registry Editor by clicking Start->Run->Regedit or simply typing Regedit into the search box on your start menu.
[step 2] Find and expand the following key:
[step 3] Backup this entire key to a file by right-clicking it and selecting Export and specifying a safe location to backup the registry file.
[step 4] You will likely notice a number of sub-keys in Configuration that look something like the screenshot below.
[step 5] Delete each of the sub-keys contained in Configuration by clicking it one by one and hitting the delete key on the keyboard and then confirming the deletion.
[step 6] OPTIONAL: I also repeated [steps 2-5] for the Connectivity sub-key because it had some of the same entries as Configuration, but this may not be necessary.
That’s it. Hope it helps someone out there.