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Questions tagged [bios]

The BIOS (basic input/output system) of an IBM-compatible PC is a ROM which performs the POST (power-on self-test), initializes the peripheral devices, and provides a basic firmware interface.

The BIOS (basic input/output system) of an IBM-compatible PC is a ROM which performs the POST (power-on self-test), initializes the peripheral devices, and provides a basic firmware interface.

Unified Extensible Firmware Interface (UEFI) was designed as a successor to BIOS, aiming to address its technical shortcomings. As of 2014, new PC hardware predominantly ships with UEFI firmware.

See also

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VT-x is not available, but is enabled in BIOS

Recently I started having an issue with VT-x on my Windows 10 running on HP EliteBook. I was using Oracle VirtualBox to run some VMs on it before and VT-x was enabled in BIOS and was working fine. I started getting VT-x is not available error every…
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What is the difference in "Boot with BIOS" and "Boot with UEFI"

Now Windows 8 supports the UEFI bootloader and I have read that its different from the BIOS, but it's unclear to me after many searches on the Google. Some points in mind are below:- As we all know, BIOS is an important part of accessing boot…
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Can't enter BIOS password containing "!"

Yesterday, I added a password containing a ! to my BIOS. Unfortunately, the password prompt that asks for the password when you boot doesn't let you write a ! (i.e. the little * isn't added and it tells me it's the wrong password). So I Googled how…
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Linux on UEFI - how to reboot to the UEFI setup screen like Windows 8 can?

makeuseof.com explains that Windows 8 certified hardware has a new way to enter the UEFI setup screen (equivalent to BIOS). From How To Access The BIOS On A Windows 8 Computer: No longer do we press a certain key during the boot process to reveal…
sourcejedi
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What are the functions of the BIOS while the operating system is running?

I always wondered whether the BIOS (apart from conducting POST, starting the bootloader and passing control to the OS after one presses the power button) has any purpose or function while the operating system is running? Does the operating system…
JohnnyFromBF
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Why is the first BIOS instruction located at 0xFFFFFFF0 ("top" of RAM)?

I know that BIOS loads its first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions and hope you can help me with some of them, at least. My questions: Why is the first BIOS instruction located at the "top" of a…
Fernando Paladini
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Where is the BIOS stored?

From https://en.wikipedia.org/wiki/BIOS: BIOS software is stored on a non-volatile ROM chip on the motherboard. ... In modern computer systems, the BIOS contents are stored on a flash memory chip so that the contents can be rewritten without…
Tim
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How is the message "Unsupported CPU installed" displayed?

I have an unsupported CPU inserted in my machine and I get this error while my PC is booting: Unsupported CPU installed. My question isn't how to fix it but rather: How is this error message displayed if the CPU is not in use? Can BIOS work without…
David
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What is the difference between BIOS and firmware?

Could anyone elaborate on the differences between BIOS and firmware please?
Koray Tugay
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How computers display raw, low-level text and graphics

My ever-growing interest in computers is making me ask deeper questions, that we don't seem to have to ask anymore. Our computers, at boot, as far as I understand it, are in text mode, in which a character can be displayed using the software…
Doddy
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What is CSM option

What is the CSM option in BIOS? If I can't boot into Windows any more, is it because CSM is disabled? Would an ASUS K55 come with this option diabled?
Ken
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What does "Legacy USB Mouse" support in a BIOS mean?

What does a "Legacy USB Mouse" option in a BIOS mean? Yes legacy usually means older revision, or obsolete. So legacy usb mouse means support for "old style usb mouses". That's not really answering the question. As Mr. Tamm, my high school…
Ian Boyd
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How to create an EFI System Partition?

TL; DR How do I create an EFI system partition from scratch? How do I put the EFI firmware on it onces it is created? Long version I hava Toshiba T430 laptop. I received it with Windows 7 installed (but I think originally it has shipped with Windows…
Alexander Popov
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Does Windows 8 support UTC as BIOS time?

Is there any way to use Windows 8 with time in UTC in BIOS? I know there is a way to do it in Windows 7 (in this question: Does Windows 7 support UTC as BIOS time?), but this solution makes my system unbootable. Windows expects the bios clock to be…
Roren
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Using virtual box is it possible to set your virtual machine time to be different from host time

Using virtual box is it possible to set your virtual machine time to be different from host time. Say 1 year into the past. If I wanted to run the windows XP images provided by Microsoft from…
nelaaro
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