ULPS usually gives more micro-stutter due to it trying to down clock the second GPU when it's not used much. Sometimes that can happen for split seconds in the game, cause lag spikes, and stutter.
So I personally always turn it off.
When you open the Driver Control Centre There's a TAB under Performance called 3D Applications.
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This is where the profiles are, to see if your game has one Click the " + Add " button and navigate to the game .exe file.
If you then select the game .exe it'll either give you a pop up saying this game already has a profile, or it won't do anything.
If it does nothing it means the game doesn't have a Crossfire Profile.
Since you've then added the game, you can choose to force a specific form of Crossfire to run.
You do this by selecting an AMD CrossfireX Mode. AFR is usually the best bet for getting crossfire working in non Xfire support games, but it can cause a lot of flickering on screen, especially on water if the game doesn't support Alternate Frame Rendering.
There's also "Use AMD Pre-desired profile" where you can type in the name of a game, and if they have a profile for it, use that profile for your current game.
An Example of that is using the Borderlands 2 Crossfire Profile for Borderlands The Pre-Sequel. As both games use the same engines, and there's a very good chance it'll work for it.
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If by then the game still doesn't use Crossfire, which you can check by using MSI Afterburner's On Screen Display to monitor GPU usage, VRAM, temps and such, it would be best to use your user created profile for the game to Disable Crossfire.
The MSI Afterburner OSD looks like this in game in the top left corner.
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Sometimes if a game doesn't support Crossfire and you force it on you get Negative scaling, where you actually get worse performance with two or more GPUs than a single one.
So disabling crossfire in that game can help.