I've been having a similar issue myself; I have two monitors and two computers, but use both monitors for each computer (one on DVI inputs, one on DisplayPort). Not finding any obvious solutions, I went ahead and tried to fix it myself :)
The end result is that I've added some code to synergy that will automatically tell your monitor to switch inputs when the mouse leaves a particular display. I'm still testing it out, but so far it's working quite well for my purposes!
I'm happy to share my changes (either in source or binary form), but you should know that it's sort of a half-baked solution that's designed more for my scenario (where all monitors are shared and I only have 2 PCs). I'm not sure if I'll ever get around to a more 'general purpose' configurable solution...
UPDATE 4/28
Since this has been working well for me, I'm happy to share out a Windows installer with my changes. Source code is available upon request in case anyone wants to improve upon this.
Download link (private build): synergy-1.4.8-Windows-x86.exe
Sample configuration file
Instructions:
- Download and install synergy-1.4.8-Windows-x86.exe from my dropbox link above. Make sure to uninstall any previous versions of Synergy.
- Copy the configuration file to the proper place on your computer, and use the Synergy UI to point it at that file.
- Update the configuration file for your system. In my default config file, I have 2 PCs (Cosmo and Pinot), and each is connected to the same 2 monitors (Cosmo with DVI-D, Pinot with DisplayPort). I have turned off the auto-mouse linking in favor of hotkeys (CTRL+F1/F2) for switching monitors/inputs. I recommend you do the same, as changing monitor inputs can take a few seconds and can only be done by the current input--so if you go back and forth across the border quickly you can get in a weird state.
I've added one new configuration property to the screens section, called monitorinput. The value is the input ID to switch to when the mouse leaves that PC (so it's a little backwards from how you might expect it to be written, as you set the input of the other PC). The values I'm aware of:
- 1: Analog (VGA)
- 3: DVI-D
- 15: DisplayPort
If these don't work, or if you have additional inputs, you can download a tool called softMCCS which will give you the DDI/CI information from your monitor, including which input IDs are supported.
As you can see from the example, I set monitorinput = 15 for Cosmo (meaning, when leaving Cosmos set the input to DisplayPort which is what Pinot uses), and monitorinput = 3 for Pinot (meaning, when leaving Pinot set the input to DVI-D which is what Cosmo uses). It only really supports two PCs at this point.
That should be enough to get you up and running; let me know if it works (or if you have issues). Hope this helps!