BIOS

BIOS

1. Basic Input/Output System

   • BIOS chip located on motherboard

2. Initializes CPU & memory

   • Makes sure you have all hardware components needed to load an operating system
     • POST
       • Power on self test
         • If any of the hardware checks fail a message pops up
       • Once POST finished it looks for boot loader to start operating system
         • Computer loads operating system normally

3. Legacy BIOS

   • Older/ Traditional BIOS
   • Operating system talked to hardware through BIOS rather than accessing it directly
     • Limited hardware support i.e modern network, video/ storage devices

4. UEFI BIOS

   • Unified Extensible Firmware Interface
     • Modern BIOS
       • Replaces Legacy BIOS
   • Can boot from larger storage systems
     • Support FAT and removable devices
       • Provides Pre-Boot environment
         • Without OS allows to browse, backup & remote diagnostics

5. Non Volatile BIOS Memory

   • Stores BIOS configuration
   • Saved to CMOS (flash)
     • Doesnt need constant power source