Hmm, I don't have your specific hardware, but...see
http://www.xfree86.org/~dawes/845driver.html
(READ IT ALL for it to make sense, you may have some work to do, I would print this one out if you don't have photographic memory),
quote from page above:
The X server driver for the 830M and 845G is part of the "i810" driver. It's only the DRI/DRM components that are different for the 830M and 845G compared with the 810 and 815. To fix this problem, make sure that your XF86Config file references the "i810" driver, not "i830". The table below summarises what is what:
Chipset X server driver DRM kernel driver
i810 i810 i810
i815 i810 i810
830M i810 i830
845G i810 i830
852GM i810 i830
855GM i810 i830
865G i810 i830
unquote
Now, there's alot of info on DRI/DRM and Intel out there, see
http://www.xfree86.org/current/Status17.html#17
http://www.xfree86.org/4.3.0/DRIcomp9.html#23
http://www.xfree86.org/4.3.0/DRI.html
http://www.xfree86.org/4.3.0/DRI10.html#30
^^^^^^Very important, read this one first^^^^^^
And hey, if you get all that working, give yourself a pat on the back!!!