Jeg har også dette problemet.. Jeg har "låst" oppløsninga til "1280x800" (Widescreen) på alle, slik:

-----
Section "Screen"
Identifier "Default Screen"
Device "Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller"
Monitor "Generic Monitor"
DefaultDepth 24
SubSection "Display"
Depth 1
Modes "1280x800"
EndSubSection
SubSection "Display"
Depth 4
Modes "1280x800"
EndSubSection
SubSection "Display"
Depth 8
Modes "1280x800"
EndSubSection
SubSection "Display"
Depth 15
Modes "1280x800"
EndSubSection
SubSection "Display"
Depth 16
Modes "1280x800"
EndSubSection
SubSection "Display"
Depth 24
Modes "1280x800"
EndSubSection
EndSection

-----

.. Men får fremdeles bare "1024x768" som valg i Screen Resolution menyen.

(Har fått til "1280x800" i Ubuntu før..)