poor tft display/misconfiguration. some hints?

[Leonardo Canducci <leonardocanducci@yahoo.it>]

A few months ago I bought a travelmate 291. I'm quite satisfied with it
except for its 15" tft display: view angle is limited (thogh still
decent) and colors and detail are really poor (that's a serious issue 
when watching videos or pictures from my camera).
I also own a 17" tft of the same brand (acer) and it's simply great so
I'd expect better performances with this display.

now some data:
This laptop has intel i855gm integrated graphics. 
I run debian sarge with custom 2.6.8 kernel and standard xfree from sarge. 
exerpt from XF86Config-4:
...
EndSection
Section "Device"
        Identifier      "intel855gm"
        Driver          "i810"
EndSection
Section "Monitor"
        Identifier      "lcd15"
        HorizSync       30-60
        VertRefresh     50-75
        Option          "DPMS"
...
	DefaultDepth    24
...

quite strange: driver is i830 (lsmod output) and not i810 (not even 
compiled).

Since intel855gm graphics adapter is quite common in centrino laptops I'd
 like some advice from other users.
I was wondering if:
- is possible that my config is wrong, and what to check for in XF86Config-4
- intel (nonfree?) driver is better than xfree's
- is there some graphics tweaking utility for linux displays 
- what the best source of information about laptop displays and linux
- anybody else is concerned with tft poor performances

bye
--
Leonardo Canducci