6189a0e8_Build_A_PC___BIOS_Settings__Comments
[Parameter] Video BIOS Shadow [Setting] Disabled [Comments] 
Your system will perform better with this setting at Disabled. As you can read in the MS Knowledge base, shadowing is not an advantage. Only enable this if you still use DOS mode a lot, where it can improve performance as it will speed up VGA BIOS (C0000-C7FFF) accesses.
Build A PC - BIOS Settings
Comments