Basically you need to enable frame buffer support at boot time in the kernel. If you edit your grub.conf (in the /boot directory), you need to find the 'kernel' line that you are currently booting as there maybe more than 1. Then add 'vga=XXX' at the end of the line. The XXX you must determine what font size you can use and support.
From experience, usually 788 works for my 17" mon which can support 1024x768.
Note I put 788 in decimal, I think the parameter also supports hex.