The document discusses the motherboard BIOS and CMOS. It describes how the BIOS is used to control and troubleshoot hardware before an operating system loads. It contains information on BIOS chips, updating the BIOS, using the BIOS setup utility to modify settings stored in CMOS, and troubleshooting hardware issues using BIOS beep codes.

1. GOHEL VISHAL H
LECTURER OF COMPUTER DEPTT.
GP BHUJ
MO.9638893297
Chapter 20 Slide 1 of 23

2. Working with the BIOS / CMOS

3. Objectives
Describe about motherboard BIOS
Explain the Preboot Environment
Explain BIOS packaging
Define CMOS
Upgrade the BIOS
Describe BIOS Setup Utility
Troubleshoot the system using the BIOS beep
codes
Chapter 20 Slide 3 of 23

4. Motherboard BIOS - I
 BIOS is a collection of programs embedded in one or
more chips
Functions of BIOS
POST Setup BIOS Bootstrap Loader
Chapter 20 Slide 4 of 23

5. Motherboard BIOS - II
POST – Tests computer’s processor, memory,
chipset, video, adapter, disk controllers, disk
drives, keyboard and other components
Setup – Enables you to configure the motherboard
and chipset settings
BIOS - Collection of actual drivers which act as a
basic interface between the OS and your hardware
Bootstrap Loader - Job of this program to load the
OS from the floppy disk or the hard disk into the
computer’s main memory (RAM)
Chapter 20 Slide 5 of 23

6. ROM Shadowing
Accesses to the BIOS code are very slow relative
to accesses to code in the system memory
Technique that is used to increase the computer's
speed
During this process the contents of a ROM are
directly copied to the extended memory.
Extended memory is given the same address as
that of the ROM. The original ROM is disabled
and the new location is then write protected
Chapter 20 Slide 6 of 23

7. BIOS Manufacturer
AMI
Award
Phoenix
MR BIOS
Chapter 20 Slide 7 of 23

8. Accessing the BIOS
Phoenix BIOS Ctrl+Alt+Esc
Ctrl+Alt+F1
Ctrl+Alt+S
Ctrl+Alt+Enter
Ctrl+Alt+F11
Ctrl+Alt+Ins
Award BIOS Ctrl+Alt+Esc
Esc
Del
AMI BIOS Del
IBM BIOS F1, F2 or F10
Compaq BIOS F10
Table 20.1 – Keystrokes to Access BIOS
Chapter 20 Slide 8 of 23

9. Preboot Environment & Dual BIOS
 Preboot environment is an environment in which various
applications can run without requiring the presence of an
operating system
 Phoenix FirstBIOS have a common preboot environment
with a graphical user interface
 This enables a user to access the BIOS setup, extended
diagnostics, a backup/restore application or a full recovery
of the original system contents
 On GIGABYTE motherboards with Dual BIOS there are
physically two BIOS chips one is called "Primary" BIOS
and the other is "Secondary" BIOS
 If your "Primary" BIOS fails, the "Secondary" BIOS
automatically takes over on your next system boot.
Chapter 20 Slide 9 of 23

10. Basic Input / Output System (BIOS) - I
 Enables you to control and troubleshoot the system and the
different hardware components before loading the
operating system
 Types of BIOS chips
• Rectangular shaped 32-pin Dual In-line Package (DIP)
• Square 28-pin Plastic Leaded Chip Carrier (PLCC)
Chapter 20 Slide 10 of 23

11. Basic Input / Output System (BIOS) - II
Runs the power-on self-test (POST) when the
system starts
Receives signals from the hardware
Loads the custom settings from the CMOS that
stores the BIOS settings
Displays the settings
Locates the bootable devices and loads the
operating system from the bootable device
Chapter 20 Slide 11 of 23

12. Complementary Metal Oxide
Semiconductor (CMOS)
 Memory chip located on the motherboard that stores the
BIOS settings
Battery must be replaced when it becomes weak or
you may lose the stored BIOS settings
Receives power from the battery that is installed on
the motherboard
 Clear the BIOS settings stored in the CMOS using the
jumpers located on the motherboard or by removing the
battery from the motherboard
Chapter 20 Slide 12 of 23

13. Backing up BIOS Settings
 To backup your BIOS, first you need to know your BIOS
company, which can be AMI, Award or Phoenix. Just pay
attention to what appears on your computer screen just after you
turn it on; the BIOS manufacturer name will be shortly
displayed.
 For AMI BIOS, Award or Phoenix BIOS, you can download the
software
 You need to unzip the downloaded file and copy the
uncompressed file to a bootable floppy disk. You need to boot
from this floppy, since the BIOS upgrading program does not
run under Windows.
 Some motherboard manufacturers have their own BIOS upgrade
software, usually Windows-based. In this case, you can use the
motherboard manufacturer software instead of the AMI, Award
or Phoenix software.
 Just perform the BIOS upgrade procedure and tell the
programming software to write your current BIOS to a file.
Chapter 20 Slide 13 of 23

14. Upgrading the BIOS - I
Two ways for
upgrading a
Motherboard BIOS
Replacing
Physical
BIOS Chip
Performing
a Flash
Update
Chapter 20 Slide 14 of 23

15. Performing a Flash Update
 Download the BIOS software from the Internet. The
software will be available in a zip file.
 Unzip the file to a folder.
 Insert a blank floppy in the floppy disk drive.
 Run the .exe file from the folder.
 Follow the steps displayed by the wizard to create a
bootable BIOS update floppy disk.
 Restart the system with the BIOS update floppy disk
in the floppy disk drive and boot the system from
floppy. The system will update the BIOS.
 Restart the system and enter the BIOS to check if it
is updated.
Chapter 20 Slide 15 of 23

16. BIOS Setup Utility
Enables you to modify the settings and store them
in the CMOS
Enables you to control the boot sequence
Changes the BIOS setting to correct any hardware
problems
Chapter 20 Slide 16 of 23

17. BIOS Main Menu Page
 Displays the different BIOS options which can be changed
Chapter 20 Slide 17 of 23

18. Standard CMOS Setup Page
 Enables you to set the basic settings of the system such as
the date and time, hard disk settings, and diskette drive
settings
Chapter 20 Slide 18 of 23

19. Advanced Setup Page
 Enables you to access the advanced functions of the BIOS
such as Boot Devices, S.M.A.R.T. for Hard Disks, Boot
Up Num-Lock, Floppy Drive Swap about the system
Chapter 20 Slide 19 of 23

20. Power Management Setup Page
 Sets the parameters such as Standby Time Out, Suspend
Time Out, Ring On Power On for the system power
management operation
Chapter 20 Slide 20 of 23

21. PCI / Plug and Play Setup Page
 Enables the system to automatically search for new
hardware connected to the system
 Automatically search for the drivers to use the device
Chapter 20 Slide 21 of 23

22. Applying Settings
Applying Optimal settings enables to set the
default options
Best Performance Settings enables to set BIOS
options to make the system perform at best level
Chapter 20 Slide 22 of 23

23. Features Setup Page
Controls the built-in motherboard components
Chapter 20 Slide 23 of 23

24. CPU PnP Setup Page
Enables to change the microprocessor settings, to
adjust the speed of the microprocessor
Chapter 20 Slide 24 of 23

25. Hardware Monitor Page
Displays the system hardware details
Enables to monitor the system to prevent
overheating
Chapter 20 Slide 25 of 23

26. Setting the BIOS Password
Protects the BIOS settings stored in the CMOS
Password option from the Advanced Setup page
should be enabled
Prompts to enter the password before accessing
the Setup Utility
Chapter 20 Slide 26 of 23

27. Troubleshooting Using AMI BIOS Beep
Codes - I
Number of Beeps Solving Problem
1 Short Beep System OK. If system does not start check that the
power and data cables are properly connected
2 / 3 / 4 Short Beeps Check that the RAM and Video Adapter cards are
properly connected.
5 Short Beeps Check that the RAM is properly installed. Check that
the microprocessor is properly installed.
Replace the microprocessor or the motherboard.
6 Short Beeps Check or replace keyboard.
Chapter 20 Slide 27 of 23

28. Troubleshooting Using AMI BIOS Beep
Codes - II
7 Short Beeps
Check the processor and heat sink are properly installed
8 Short Beeps Check that the video card is properly installed.
Replace the video card.
9 Short Beeps Check that the BIOS chip is properly connected.
Update or Replace the BIOS chip.
10 Short Beeps Replace the battery or CMOS chips.
11 Short Beeps Check the cache settings from BIOS and check that the Cache
memory chip is properly connected.
Replace the Cache memory chip.
1 Long, 3 Short Beeps Check that the RAM is properly connected.
1 Long, 8 Short Beeps Check that the video card is properly installed.
Replace the video card.
Chapter 20 Slide 28 of 23

29. Summary - I
BIOS software enables you to control and
troubleshoot the system
Types of BIOS chips include Dual In-line Package
and Plastic Leaded Chip Carrier
BIOS run the power-on self-test when the system
starts
CMOS stores the BIOS settings
Updating the BISO adds additional functions to the
BIOS and it also fixes all the errors and bugs in the
BIOS
Chapter 20 Slide 29 of 23

30. Summary - II
BIOS Setup Utility enables you to modify the
settings and store them in the CMOS
The BIOS Setup Utility Main menu page displays
different BIOS options that you can change
BIOS password used to protect the settings stored
in CMOS
You can troubleshoot the system using the BIOS
beep codes.
Chapter 20 Slide 30 of 23