Comment 38 for bug 129380

I don't really recommend doing this for the current intel ubuntu
package, given the bugs I mentioned above. Also, (according to the xorg
mailing list) there are some performance regressions and other
problems... Things should improve when version 2.2.0 of the driver is
released. Also, it's not easy to download if you're unhappy with the
new server.

If you still want to upgrade to this package (or something else from
hardy), here's how:

Go to synaptic, settings->repositories->third party software->add

Enter this into the dialog with this (one line):

deb http://www.gtlib.gatech.edu/pub/ubuntu hardy main restricted
universe multiverse

or with this:

deb http://mirrors.kernel.org/ubuntu hardy main restricted universe
multiverse

(you can replace the url with your favorite ubuntu mirror if you want)

Hit OK through the dialogs, and click "reload". Upgrade just the
xserver-xorg-video-intel package and any dependencies synaptic says need
to be updated.

Hit apply. Once it's done, go back to settings, and uncheck the entry
you created for hardy. Otherwise, when you update your system, it'll
upgrade everything to hardy versions (which might be what you want...).

You can also selectively upgrade by editing /etc/apt/preferences, or
messing with settings->preferences->distribution in synaptic. Look
online for more info.