I have been using grub to multiboot successfully for years and I think I understand fairly well what I am doing. Awhile back my display went belly up so I started using my HDTV as a display through it's VGA port. It seems to work OK except that grub will not display it's menu on boot up. I get a little box with the message "mode not supported". If I just wait it will boot my default OS, presently fc15. Or I can blindly hit the down arrow a few times and eventually get the OS I want.
 I have looked at my BIOs setup, but I don't see anything that looks promising. Also I couldn't find any thing on Google. I would appreciate any help.