On Dell XPS M11530 with Bios  A08, The following line to the kernel in
/boot/grub/menu.lst needs to be set for the trackpad to not go Bersek
<pre>
i8042.nomux=1
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Also, to enable scrolling, edit /etc/X11/xorg.conf, under “Input Device” section,
<pre>
Section “InputDevice”
Identifier “Synaptics Touchpad”
Driver “synaptics”
Option “SendCoreEvents” “true”
Option “Device” “/dev/psaux”
Option “Protocol” “auto-dev”
Option “ZAxisMapping” “4 5″
Option “Emulate3Buttons” “on”
Option “SHMConfig” “on”
Option “VertEdgeScroll” “on”
Option “VertTwoFingerScroll” “on”
Option “LeftEdge” “85″
Option “RightEdge” “910″
Option “TopEdge” “85″
Option “BottomEdge” “715″
Option “FingerLow” “25″
Option “FingerHigh” “30″
Option “MaxTapTime” “180″
Option “MaxTapMove” “220″
EndSection
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