okay this is the problem..i have a gateway laptop.the screen on it all of a sudden it went black i couldnt figure it out.so i got it repaired.and they put a new screen.a week later it broke again..
so i just connect a external monitor..

can i still reinstall windows even if the mounted screen doesnt work.because you cant see the bios with the external monitor..

any help

You can't see CMOS (BIOS)? well my computer can... Go ahead reinstall your windows. No probs. But i'm not that sure.