Option name:
Async GFX Clock Source
Possible values of an option:
[14.318 MHz OSC], [100 MHz PCIE]
The option description:
If you selected an asynchronous operation mode of the integrated drawing, specifies, whether will be as reference frequency for the integrated graphic kernel to be used standard frequency in 14.318 MHz ([14.318 MHz OSC]) or frequency of bus PCI Express ([100 MHz PCIE]). More preferably the first variant.