Not applicable

Inspiron 1750, Windows 10, Black screens on reboot

Have updated my Inspiron 1750 from Windows 7 to 10 and everything went just fine except for black screens showing up for about 30-45 secs when rebooting slowing down process. Somehow I remember that I had that same problem at the very beginning with Windows 7 but can't remember what he solution was. Any suggestions? Thanks