Choose this option if you have a system that has Intel 830M, 845G,
852GM, 855GM 865G or 915G integrated graphics. If M is selected, the
module will be called i915. AGP support is required for this driver
to work. This driver is used by the Intel driver in X.org 6.8 and
XFree86 4.4 and above. If unsure, build this and i830 as modules and
the X server will load the correct one.

source code:

drivers/gpu/drm/i915/