gamepc@firefly ~ $ DISPLAY=:0 xrandr 
 SZ:    Pixels          Physical       Refresh
*0   1280 x 1024   ( 307mm x 230mm )  *47   43  
 1   1152 x 864    ( 307mm x 230mm )   60   47   43  
 2   1024 x 768    ( 307mm x 230mm )   75   72   70   60  
 3    800 x 600    ( 307mm x 230mm )   75   72   70   60   56  
 4    720 x 576    ( 307mm x 230mm )   60  
 5    640 x 480    ( 307mm x 230mm )   75   72   60  
 6    640 x 400    ( 307mm x 230mm )   75   60  
 7    400 x 300    ( 307mm x 230mm )   75   60  
 8    320 x 240    ( 307mm x 230mm )   75   60  
 9    320 x 200    ( 307mm x 230mm )   75   60