What Is Shadow Ram?

Asked 06-May-2022
Viewed 243 times

1 Answer


  • Shadow RAM is a copy of the Basic Input/Output Operating System (BIOS) routines from read-only memory (ROM) to a dedicated region of random access memory (RAM) for faster access. Shadow RAM access typically takes 60-100 nanoseconds, whereas ROM access takes 125-250 nanoseconds.
  • Certain BIOS routines are used not just during the boot or startup of the system, but also during normal operation, particularly to drive the visual display terminal, in some operating systems such as DOS. However, these methods are not used in Windows or OS/2, and shadow RAM is not required. The use of shadow RAM can be turned off or on in some systems.

Read More: What Is Tras?