small screen area on Toshiba Satellite

[Ray Lozano <raylozano@gmail.com>]

I recently installed Debian 3.1 on my Toshiba 2405-S201 which has a S3 SuperSavage IXC1179 video card. 

Most things work pretty well so far, but the "live" area of my screen is smaller than it should be. I have no problems with font sizes or graphics. In fact, I am using 
 the Epiphany browser to create this message.

The machine has been running Win XP Pro for years and now dual boots successfully. I used Knoppix to resize the NTFS partition.

While XP still fills the entire screen display area of about 11" x 8"
as normal, Linux text mode and X both occupy an area in the middle of
the screen about 8" x 6" with thick black borders ("dead" area) filling
in the rest. 

I added the DisplaySize line (which was not created by the
installatiion) to my XF86Config-4 file, but that didn't make a
difference:
Section "Monitor"
    Identifier    "Generic Monitor"
    HorizSync    30-60
    VertRefresh    50-75
    Option        "DPMS"
    DisplaySize    285 212
EndSection
 
I have looked everywhere for ideas on how to expand the live area to
the full dimensions of my screen but have not found anything. 

Any help will be appreciated.

Thanks for your time,
Ray