So I am currently working on 2 different older HP computers. This one is a quad core a6650f. I already reinstalled Windows 10 on it with a USB thumb drive I used for the media creation tool through Microsoft about 7 months ago. I recently decided to switch out video cards from a GT 740 4gb back to the HD 6450 1gb as it will only be used to occasionally play old games. Long story short I cannot completely uninstall the Nvidia drivers so there is screen flickering going on, etc. I have very little if any vital personal stuff on this pc so at this point I figure just do a full reinstall of Windows 10 again. Problem is that the computer is not automatically booting from the USB drive as it did last time I did this, and when I go to boot options and choose USB to boot from I just get the black screen with flashing cursor and goes nowhere. This is the same USB drive I used on this same computer so not sure what the issue is. I can go to system restore and choose to reset the PC using CD, USB, etc., but not sure if that will get me the same results. I am striking out on all fronts here. Anyway any suggestions would be greatly appreciated.