Intel doesn't make discrete graphics, but they make a hell of a lot of integrated graphics chips. The linked website lists the chipsets for which the open-source drivers are published: Supported Hardware and Driver Documentation The Linux graphics drivers from Intel support the following Intel® chipsets:
Short name Full name
965G G965 Integrated Graphics Controller
965 Q963/Q965 Integrated Graphics Controller
946GZ 946GZ/GL Integrated Graphics Controller
945G 945G Integrated Graphics Controller
945GM Mobile 945GM/GMS/940GML Express Integrated Graphics Controller
915G 82915G/GV/910GL Express Chipset Family Graphics Controller
915G 82915G Express Chipset Family Graphics Controller
915GM Mobile 915GM/GMS/910GML Express Graphics Controller
865G 82865G Integrated Graphics Controller
855GM 82852/855GM Integrated Graphics Device
852GM 82852/855GM Integrated Graphics Device
845G 82845G/GL[Brookdale-G]/GE Chipset Integrated Graphics Device
i830M 82830 Chipset Graphics Controller
815 82815 Chipset Graphics Controller
810 82810 Chipset Graphics Controller
810-DC100 82810-M DC-100 System and Graphics Controller