Small screen on boot, problem

[augustofr]

   When i first install debian on my laptop, the screen becomes very small, 
just a little
quadrate. I resolved that putting in lilo.conf "vga=791". So i moved to GRUB, 
but how i enter this vga=791 with grub ? And is there another way to resolve 
that problem ? My card is a Trident CyberAlladin, i compilled the kernel 2.6.5 
that have support for Trident cards. Thanks.