This case is unlikely to occur, but is documented for the sake of completeness.
In this situation, the driver will probe the adapter for clock frequencies unless XF86Config clocks are already specified. In either case, the driver will then attempt to normalize the clocks to one of the following specifications:
BIOS setting 1: Clocks 0.000 110.000 126.000 135.000 50.350 56.640 63.000 72.000 0.000 80.000 75.000 65.000 40.000 44.900 49.500 50.000 0.000 55.000 63.000 67.500 25.180 28.320 31.500 36.000 0.000 40.000 37.500 32.500 20.000 22.450 24.750 25.000
BIOS setting 2: Clocks 0.000 110.000 126.000 135.000 25.180 28.320 31.500 36.000 0.000 80.000 75.000 65.000 40.000 44.900 49.500 50.000 0.000 55.000 63.000 67.500 12.590 14.160 15.750 18.000 0.000 40.000 37.500 32.500 20.000 22.450 24.750 25.000
BIOS setting 3: Clocks 0.000 0.000 0.000 0.000 25.180 28.320 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 12.590 14.160 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000If the driver matches the clocks to the third setting above, functionality will be *extremely* limited (assuming the driver works at all).