Lesson 6 Chapter 4 - BIOS/UEFI Flashcards
What is the boot process?
steps, after, before
The steps your computer goes through after you press the power button but before the OS appears on the monitor
What components make up the boot process? (4)
system, built in, config, eraser
- System ROM chip (mostly permanent, firmware)
- BIOS/UEFI (programming built into the ROM chip to support components)
- BIOS/UEFI configuration options
- NVRAM
What does the system ROM store? For what type of computer?
The system ROM stores all absolutely essential programming that a computer needs (any computer, mobile device, old and new, etc)
What does the BIOS/UEFI provide for the computer? (2)
amnesia, provides
- Provides system information (what type of computer, what hardware is in it, what day/time it is)
- Provides support for all the motherboard components/things that are plugged into the motherboard
What does CMOS stand for?
Complementary Metal Oxide Semiconductor
What’s the difference between the ROM-BIOS chip and the CMOS chip? (BIOS 1, CMOS 3)
bios: stores
cmos: load, rely, contain
The ROM-BIOS chip:
- Stores BIOS settings from the motherboard’s manufacturer
CMOS chip:
- Loads any exceptions/changes to the BIOS’s basic facts (overwrites)
- The CMOS chip relies on a battery to keep it powered
- Contains a special kind of Dynamic RAM that requires very little electricity
What does NVRAM stand for?
Non-Volatile Ram
What is NVRAM used for? What doesn’t it rely on?
NVRAM replaced the CMOS chip, and provides the custom settings for a computer along with the system ROM without relying on a power connection
In today’s modern systems, which bootup processes are still used and for what? (3)
- System ROM - absolutely essential programming
- BIOS/UEFI - basic system information, hardware, day/time (CMOS), support for motherboard components
- NVRAM - exceptions/changes to BIOS/UEFI
On older systems, what were the 2 choices for data stored on chips?
- System ROM/BIOS (read-only, unchangeable)
- CMOS (chip remains constantly on to retain its data)
How many bits make up a BIOS chip, and a UEFI chip? (2)
BIOS chip - 16 bits
UEFI chip - 32 bits
Why did manufacturers start making motherboards with a UEFI chip instead of a BIOS chip?
UEFI chips because it’s 32-bits and is able to store more data that the 16-bit BIOS chip can’t
What are some differences between BIOS and UEFI features? (4)
chip, gpu, bytes, shoe
- 16-bit BIOS, 32-bit UEFI
- UEFI offers a GUI to allow navigation with a mouse
- Supports booting drives larger than 2.2 TB by using the GPT standard
- Supports Secure Boot feature
What are the 3 main stages of the boot process?
fight the, office, weight
- Power on
- POST
- OS loads
Where is the power good wire located? What uses the power good wire to wake the system up?
The good wire is located on the CPU
The power supply uses the power good wire to wake the CPU and system up (so the CPU can communicate with the system ROM chip and start the BIOS/UEFI programs)
What happens during POST? (3 parts)
asks, run-report, error user
- BIOS/UEFI asks essential hardware to identify itself
- Runs internal diagnostic routines and reports back to the BIOS/UEFI
- If there are any device errors, the BIOS/UEFI communicates it to the user with POST error codes