My laptop has an Intel HD 4000 hand an nVidia GT650M. I installed the new Windows Server 2012 and the up-to-date drivers (220.127.116.1117 for HD 4000 and 18.104.22.1687 for GT650M). But only the HD 4000 is working, while in device manager, there is a yellow "!" on GT650M, reporting "Windows has stopped this device because it has reported problems(Code 43)". How to resolve this problem? Thank you.