That would depend on a few things.
What exactly is your setup? How many monitors, what are they connected to?
DeskScapes will only use a GPU thats physically attached to a monitor that it is displaying on. If you have a SLI setup then it may be it is using the GPUs in SLI mode in which case that would be something that would need to be changed in your graphics cards settings app. The processes would be DSHost.exe and DeskscapesConfig.exe.
The other possibility is the monitoring software is simply incorrectly reading usage on both when it is only on one.
