I am not sure that FreeBSD 8.2 will fully support this card. The Xorg version for FreeBSD is 1.7.7 and the ATI driver used is version 8.881. This wikipedia article indicates that cards up to R3XX are supported fully. The article indicates 2D support for R4xx and R5xx
Radeon Wiki
OpenBSD has support
OpenBSD ATI 4650
Distrowatch is helpful as it lists the xorg version and ati drivers that are utilized in the three major BSD variants. Also, each BSD does have a hardware support page