I know this has been posted by others but I wanted to add my vote to this too.
I run three monitors in Eyefinity, but I still have games that do not run in 5760x1080, that require me to switch back to a single monitor or extended desktop.
In Catalyst Control Center, I used to have three presets to enable me to do this.
Now, in Crimson 16.3.1, the option to disable individual monitors or switch between presets, has gone.
Yes, the Presets option is still in the menu, but it is no use as there is only Eyefinity, and options associated with it.
Please, please, bring back the previous options so that I can easily switch to single monitor gaming when necessary.