I would test this issue with the latest Gutsy Live CD. You have to change to Intel driver manually until https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/135141 this bug is fixed but with the Intel driver you have good changes that your external monitor works out of the box.
I would test this issue with the latest Gutsy Live CD. You have to change to Intel driver manually until https:/ /bugs.launchpad .net/ubuntu/ +source/ xorg/+bug/ 135141 this bug is fixed but with the Intel driver you have good changes that your external monitor works out of the box.