BIOS shadow
The process of the contents of the ROM being copied to the RAM allowing the computer to access that information quicker. This process is also known as Shadow BIOS ROM, Shadow Memory and Shadow RAM.Below are examples of messages commonly seen when the computer is first booting indicating that the portions of a ROM are being copied to the system RAM.
System BIOS shadowed
Video BIOS shadowed
Some computer BIOS setups may allow the user to enable and disable this feature. We recommend that it is left enabled; disabling this option could cause problems with some computers.