dontlistentome :
Yeah, you really should uninstall the software related to the card you are no longer going to use. Just be careful if you have an AMD motherboard, there are likely chipset drivers from AMD that you need. Make sure you delete videocard drivers and software only, if that's the case.
Thanks for responding quickly, I don't know what my motherboard is, but my processor is an AMD FX-770K Quad Core Processor, so I'm not sure what I should uninstall, there are two AMD programs in programs and features (AMD Install Manager and AMD OverDrive). Do you know what I should do?