FreeBSD
FreeBSD is an advanced operating system for x86 compatible, DEC Alpha, IA-64, AMD64, PC-98 and UltraSPARC® architectures. It is derived from BSD, the version of UNIX® developed at the University of California, Berkeley. It is developed and maintained by a large team of individuals.
Status
The mga, r128, r200, radeon, tdfx, and sis drivers are all supported on FreeBSD. i810, i830, and gamma drivers aren't yet.