$ ls -l /dev/dri
total 0
crw-rw----  1 root  wheel  180, 0 Apr 27 22:27 card0
crw-rw----  1 root  wheel  180, 1 Apr 27 22:27 card1
crw-rw----  1 root  wheel  180, 2 Apr 27 22:27 card2
crw-rw----  1 root  wheel  180, 3 Apr 27 22:27 card3