Re: intel error
First do the "Clean uninstall" and only then install the New driver!
1) You can try to do a "clean uninstall" manually like described e.g. here;
2) Or you can help your self to clean all old driver's leftovers with a third party software tool like e.g. Display Driver Uninstaller (you can download it from here or here);
3) Optional: Just to make it sure, you can run this tool two times: do it first time, restart a computer; and then run it for second time 🙂
4) After second restart you can finally try to install the new driver properly!
p.s. DDU tool is really great. I have used it many times without any problems. Easy to use.