HD Install :: Display setting

I've put DSL on an old Toshiba Satellite Pro 460 (PII I think, about 165Mhz) in a HD install. The display size isn't detected properly, so the boot text is always running off the bottom of the screen (which makes it a bit tricky if it is prompting for something), and when loaded the display area is larger than the screen - the bar which is normally near the bottom is missing, and the mouse can move off the bottom or right hand sides.

How can I change the display setting or detection of screen size?? It should be 800 x 600.

I did have a previous install of Slackware with Lilo on this machine, could that be part of the problem?

Many thanks
Peter

Sorted - lilo.conf had the line

vga=791

in it - changed this to vga=788, ran lilo and everything is now ok.

800 x 600 modes:

colours | code

256 | 771
32,768 | 787
65,536 | 788
16.8M | 789

original here.