I tried getting widescreen working on my Acer Travelmate 4102WLMi using SLackware 10.1 when I found this rather excellent article by Tim having a Sony laptop with pretty much the same configuration :
http://linux-laptop.net/hosted/fs215e-slackware.html
Did everything he had written (kernel 2.6.13, xorg-6.8.99.16) but still no success. Kept getting messages like

(II) I810(0): Not using mode "1280x800"

in Xorg.0.log. Setting modeline and usemodes by generating the settings from
gtf 1280 800 60 -x resulted in the same error message.

Also DDC kept altering my refresh ratings as so :-
(II) I810(0): Using detected DDC timings
(II) I810(0): HorizSync 48-50
(II) I810(0): VertRefresh 59-61
(WW) I810(0): config file vrefresh range 50-60Hz not within DDC vrefresh range 59-61Hz

So I added in the line "NoDDCValue" "1" in xorg.conf and then was able to manually set the VertRefresh and HorizSync ranges.
Though Tim's Xorg.0.log shows that his X is detecting his monitor settings perfectly :-
Mode: 60 (1280x600)
Mode: 63 (1280x800)

I seem to be getting
Mode: 60 (0x0)
Mode: 63 (0x0)

This only results in X not being able to find the proper mode and so starting up at 1024x768 resolution which looks really crappy on a widescreen.

(II) I810(0): LCD: Using hsync range of 48.00-50.00 kHz
(II) I810(0): LCD: Using vrefresh range of 59.00-61.00 Hz
(II) I810(0): Not using mode "1280x800" (no mode of this name)
(II) I810(0): Not using mode "800x600" (no mode of this name)
(II) I810(0): Not using mode "640x480" (no mode of this name)
(1280x800,LCD) mode clock 100000MHz exceeds DDC maximum 80MHz
(800x600,LCD) mode clock 100000MHz exceeds DDC maximum 80MHz
(640x480,LCD) mode clock 100000MHz exceeds DDC maximum 80MHz
(--) I810(0): Virtual size is 1024x768 (pitch 1024)
(**) I810(0): *Built-in mode "1024x768"
(--) I810(0): Display dimensions: (330, 210) mm
(--) I810(0): DPI set to (78, 92)


I am getting the idea that X is having problems with the LCD on the laptop. Since the Xorg.0.log shows that the 915GM chipset is detected perfectly. Any idea of a workaround / solution ??

I'm having exactly the same problems on a Dell Inspiron 1300 with WXGA 1280x800. Using SUSE 10.0 with X Server 6.8.2.

I generated the corresponding ModeLine for 1280x800 with gtf 1280 800 60 -x, got the same results.

There's no way using the standard modification of xorg.conf that X Server can display 1280x800.

Did you manage to have any success? This is extremely annoying.

Thank you.

I found a hack that helped me out.
You can find it here:
http://www.geocities.com/stomljen/

Everything else I tried on my 915M Intel Graphics card failed completely. Maybe this will help you out.

Yeah ... I installed on Dell Inspiron 300 with
http://perso.orange.fr/apoirier/
just download, compile, and replace some resolution with desired.

The problem is that there is no resolution (1280x800 etc) in BIOS, which Xorg is trying to use.