You can have 2 cards in the same machine, but you can't use non-compatible cards at the same time.
IE You can have a Dual Boot system, one partition has the FirePro installed and the Radeon disabled, the other partition has the FirePro disabled and Radeon installed. This would definitely be the easiest way to go, since you disabling it in Windows should prevent it from trying to use it. The big thing is that you'll have to swap monitors if you only have one, but it saves swapping cards out for sure. Otherwise you're doing driver uninstall/reinstalls all the time.
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