BIOS + Booting Flashcards
What does BIOS stand for?
Basic Input/Output Service
What is BIOS?
A software that helps initialize hardware and gets the operating system up and running. It’s stored in the ROM (read-only) memory chip, and NOT in the hard drive. The ROM chip is non-volatile (called firmware) and won’t erase the data once the machine is turned off. BIOS programs enable interaction with the motherboard before the OS loads.
What are the differences between BIOS and device drivers?
BIOS programs make hardware functional, while device drivers make hardware function WITH an operating system (OS) attached.
POST (Power On Self Test)
- POST routines are built into firmware with BIOS.
- POST performs diagnostics prior to the computer booting an OS. It only TESTS hardware. It doesn’t enable it.
- It broadcasts a message to the parts of the computer, checks RAM, CPU, video cards, etc.
- It will not run at all without a CPU installed, and it will not generate any beep codes in this case.
What do “NO RAM” beep codes from POST codes sound like?
They will keep beeping until you turn off the system. They tell you you have no storage.
What does one beep mean in POST?
The system is booting successfully.
What does a two beep code mean with POST?
There’s some error.
What are POST cards on the screen?
They’re two digit values that display on the screen when the system is booting.
For example: “2b-2f” could mean “memory initialization error”.
They’re useful for a system failing to boot, no sounds or BIOS, and “dead” computers.
What is System Setup?
The interface that we go to, to make changes to the BIOS and devices attached.
You can press certain keys like F2 and Delete before the system boots up.
System Setup is part of the firmware that enables changes to CPU frequencies, RAM timings, BIOS passwords, booting options, etc.
You’ve made a lot of changes in System Setup that you want to undo. What would you do then?
You can click “Default” or “Reset System Setup” to undo every change you just made. Also, you can Exit without Saving your changes.
What does a user password do in System Setup?
Prevents the OS from booting until the password is entered.
What does the administrator password do in System Setup?
prevents access to the setup program until the password is entered.
UEFI (Unified Extensible Firmware Interface)
The most modern and pre-dominate BIOS interface. It has better support and compatibility for newer hardware. It replaced traditional 16 bit BIOS in modern systems. Most hardware has UEFI built in.
What is the CMOS Battery on the motherboard?
A type of memory chip that stores basic data about booting of your computer like the date, time, and startup options chosen. CR2032 is the standard CMOS battery.
A weak or failing CMOS battery usually shows up as 20 minutes late or time is lagging behind.
RTC (Real Time Clock)
keeps the system time without any external power (aka when your system is shut off).
