Downgrading OS Samsung notebook

[rotten mac]

Hi guys.. I have samsung np900x4d, series9. It has pre installed windows8, but i like to downgrade it to windows7... I can't make it to boot in my external dvdrom with win7 cd... What can be the solution to this? thanks in advance

 

[Paul NZ]

Does the external appear in the BIOS to boot from?. And is it USB 2 or 3? If it's plugged into a USB 3 port plug it into the USB 2 port.

And since it had Windows 8 on it, you may have to disable secureboot in the BIOS if it's there. Since Windows 7 (I think) doesnt support Secureboot

 

[Alabalcho]

Before starting the downgrade, make sure you have created recovery USB / DVD so you can return to WIndows 8 if Windows 7 does not work for you.

YOu also want to make sure that there are drivers for Windows 7 for your laptop.

 

[rotten mac]

Does the external appear in the BIOS to boot from?. And is it USB 2 or 3? If it's plugged into a USB 3 port plug it into the USB 2 port.

And since it had Windows 8 on it, you may have to disable secureboot in the BIOS if it's there. Since Windows 7 (I think) doesnt support Secureboot

yes its detected on the bios, it appears in the boot priority option(which i make the 1st option)... and i also disable secureboot