ASROCK X99 OC Formula User Manual page 116

CSM (Compatibility Support Module)
CSM
Enable to launch the Compatibility Support Module. Please do not disable unless
you're running a WHCK test. If you are using Windows 8.1/8 64-bit and all of your
devices support UEFI, you may also disable CSM for faster boot speed.
Launch PXE OpROM Policy
Select UEFI only to run those that support UEFI option ROM only. Select Legacy
only to run those that support legacy option ROM only. Do not launch?
Launch Storage OpROM Policy
Select UEFI only to run those that support UEFI option ROM only. Select Legacy
only to run those that support legacy option ROM only. Do not launch?
Launch Video OpROM Policy
Select UEFI only to run those that support UEFI option ROM only. Select Legacy
only to run those that support legacy option ROM only. Do not launch?
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