13 - BIOS, CMOS, UEFI, and the Boot Process
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- čas přidán 26. 07. 2024
- This lesson covers the fundamentals of the BIOS, CMOS, newer UEFI BIOS, and how a computer performs it's Power-On Self-Test and the boot process.
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UEFI Unified Extensible Firmware INTERFACE
Air ship
Your lessons are a breath of fresh air on CZcams. The know-it-all, class clown attitude of some of these gamer bro's is crrriiiiinnnngggggyyyy
Cars
CMOS is *VOLATILE* memory. Non-volatile memory is stuff like Flash or EEPROM, which remembers data when you remove the power.
Some ATXs have embedded battery for the CMOS unlike what you would typically see with the CMOS battery. Usually volatile memory is regarded to the actual power supply of the PC and not internals; hence why ram is volatile and a hard drive is not.
awesome learning video Jason. Appreciate it mate.
Great & thorough explaination, thanks!
this is way better the professor maser videos
Excellent video - most informative. Thank you very much!
Thank you. Better explanations than most other videos
nice work done
HAL (Hardware Abstraction Layer) . A part of MS Windows and other OS. Usually it is the part of your OS that has some management of, or direct control over, your physical hardware in some way. I am not a programmer so that is the best way that i could only guess at the specifics of what HAL is or does.
i am looking to understand the EFI shell that activates when you try to enable uefi for uefi booting. Yes i know it is done not by enabling EFI but rather by managing setting of the CSM (Compatibility Support Module) in your UEFI style BIOS.
HAL is not a trick answer, it is Hardware Abstraction Layer.
THANKS
I have a question if I set a password for the BIOS and I forgotten it shall I remove the CMOS battery to make the BOIS memory for get about the last settings I did, so on with it the Password?
That usually will work to reset the password. The other option is a RESET jumper on your motherboard, depending on your computer.
Any idea why the bios settings aren't stored on the ROM? There must be a good reason for using a separate chip
Thanks a lot for this
late reply
but its because its read only memory (ROM)
you would not be able to configure the settings on a ROM chip because you can only read the data from a ROM chip
Needs revision, contradictory information observed.
C'mon, man...no one caught the Mystery Science Theater 3000 slip? I caught it, Sigmund :-)
Quantum
That funny error @4:40 if there is a keyboard error, how can i press F1 or F2
You can’t press the keys, you have to STRIKE them.
This question really bugs me ! Its like the only way to get it right is if someone told you what they think the answer is. Bios is a flashable memory and the only way to really configure the bios is to flash it. then I would be configuring it. otherwise if I am doing any configuring its the CMOS that gets configured. When I set the time I believe I am using a chunk of memory on the computer that was received from the bios. The bios then is like a hard drive that can not easily be changed.
thank you a lot! i am a beginner at bios at this stage , i gained something from nothing and i continue to build my knowl. if you have additional send me .
When settings are configured they are stored in the CMOS- Really we are changing the cmos and those settings are helf inside the cmos. Its a grey area and A unfair question that is not blatantly described. The bios is not within the cmos and there are no settings in the master boot record that HAL is hardware extraction layer. Its just really hared to get all this stuff strait.
So you are saying UEFI is just a fancier BIOS? Not sure I got it right but if so, this is completely wrong.
Thank you for your reply. I understand your point, just raising a ball here. Maybe you should make it more clear that UEFI has a completely different and well defined specification (it has one, unlike BIOS!). In short, they have the same purpose but are two distinct beasts.
All in all, your class is very clear and useful. Congrats! :)
Dude, the answer is CMOS. you even said, BIOS is where its stored, CMOS is how you configure BIOS.
This has really confused me and I can't find an answer. Can anyone explain how it's the bios and not the cmos, as you can't directly alter the bios
incorrect, you dont configure boot settings on the CMOS you do it in the BIOS