i have recently rma a gtx 960 and is being fixed right now, this means i need a replacement gpu and i dont have an igpu as i have an amd athlon 860k. my replacement is a gts 250 which can play some basic game such as hearthstone,rocket league and csgo. However when i i start up my pc it says their is a problem. the reason why their is a problem is because my gtx 960 drivers are still in the pc and are getting confused with the gts 250, i cant start windows and i need to find a way to uninstall the drivers. please help.