Committed to the
RadeonHD driver tree today is a new utility for testing the status of connectors on R500 and R600 graphics cards. This utility is called
conntest and inside the xf86-video-radeonhd branch it is found inside
utils/conntest. With root privileges, to execute conntest just run it with the PCI tag argument when your monitor(s) is connected to the different video output ports. Conntest should help the RadeonHD developers in working out the connection issues for the R500 and R600 GPUs due to four different outputs (DACA, DACB, TMDSA and LVTMA). Check out the RadeonHD driver's git code for the latest information.