Toshiba Satellite P855 won't let me out of reboot and select proper boot device or insert boot media in selected boot device and press key. I can not, I repeat I can NOT get into BIOS. No matter what key(s) I press it just scrolls "reboot and select proper boot device or insert boot media in selected boot device and press key". I replaced hard drive , same thing. Now it had Windows 8 and upgraded to 10. I have a Windows 7 disk. Do I NEED a Windows 8 or it matters not Thanks