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.

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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 ...
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8answers
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Where is the BIOS stored?

From http://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 ...
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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 ...
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9answers
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Why must a computer have a BIOS?

The BIOS software is built into the PC, and is the first code run by a PC when powered on ('boot firmware'). When the PC starts up, the first job for the BIOS is the power-on self-test, which ...
31
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5answers
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Why should I choose (or not) AHCI over IDE in my PC's BIOS settings?

I've noticed in the BIOS settings of the newer PCs I own that I can configure the drive controller work either in AHCI (Advanced Host Controller Interface) mode, or else in IDE mode. I'm suspecting ...
30
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12answers
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If USB is not listed in BIOS as a boot option, does that mean the machine can't boot from USB?

I just purchased an Asus Zenbook Prime UX31A-DH51 with Windows 8. I want to wipe the drive and do a clean install but USB is not listed as a boot option in the BIOS. Does this mean it is not possible? ...
30
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3answers
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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 ...
28
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3answers
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What is a “Programmer” in the context of Bios Recovery?

I was reading about BIOS recovery and ran across the word "programmer". (No, it's not talking about people.) What is it referring to?
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9answers
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Is it possible to recover a computer from a failed BIOS update?

While attempting the update the BIOS on an Asus motherboard, i learned the Asus Update Utility for Windows doesn't fully support Windows 64-bit. It was able to erase the BIOS without problems, but ...
25
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1answer
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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 ...
23
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2answers
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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, ...
22
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2answers
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Does the BIOS have some sort of generic 'drivers'

How does the BIOS control I/O devices without any form of drivers? For example how is an image displayed whilst the computer is booting if the BIOS doesn't have any drivers for the graphics card. ...
21
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3answers
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Why do we need a boot loader?

After the BIOS, or something similar that serves as a firmware, is started, the control is passed to the bootloader, as far as I know. Why can't the BIOS load the OS kernel directly? Also, the ...
20
votes
2answers
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What is “flashing the BIOS”?

What does "Flashing the BIOS" mean? Are there benefits to flashing it? Is it safe? Should it be done inside or outside of an OS, for example my current Windows 7 installation?
19
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3answers
31k views

VT-x/AMD-V hardware acceleration not operational with VirtualBox

I am trying to install OS X with VirtualBox, on my Windows 7 laptop. I see the following error message: VT-x/AMD-V hardware acceleration has been enabled, but is not operational. Certain guests ...
19
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2answers
202k views

Asus UEFI/BIOS options - How to boot from DVD?

I just bought a new PC and the default installed OS is Windows 8. I want to install Windows 7 but when I go into the boot options screen I only have one option: Windows Boot Manager I can't find my ...
16
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8answers
978 views

How do you explain what the BIOS is to non-Super User?

In a particularly nerdy Facebook status update I mentioned that I had flashed my BIOS. One of my friends asked what the BIOS is. My question is: How do you explain what the BIOS is and does to a ...
16
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7answers
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How can I take screenshots of the PC before it boots up?

How can I take a screenshot of the PC before it has started up? For example: If I wanted to take a screenshot of my BIOS and send it to the Network Admin for review Windows installation screenshots ...
15
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6answers
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How to prevent Windows 7 from reading the BIOS time?

I'm using the "Time Limit" feature of Windows Live Family safety. I've placed a time restriction on my computer from 12 AM to 4 AM. However if someone changes the BIOS time, the Windows time will be ...
15
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5answers
661 views

Do POST beep codes also generate a numeric code for a POST test card?

My wife is an American Sign Language interpreter. She is currently interpreting for a student in a computing class. Today they were talking about BIOS and POST beep codes and the student asked the ...
14
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6answers
9k views

Last BIOS time on Task Manager

Can someone tell me what that Last BIOS time is on the upper right corner of the task manager on Windows 8 Pro? Mine has always been 0.0. I guess it is not measuring the BIOS time properly so what can ...
14
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1answer
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What hardware device used to eat up 1.4GB of my 4GB RAM, and now suddenly after no hardware changes eats up 2.2GB?

This is more or less a continuation of What hardware device eats up 1.4GB of my 4GB RAM? While I have more or less accepted the solution there that for some mysterious reason, after a BIOS upgrade ...
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8answers
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Can a virus melt the CPU?

I was just wondering if a virus could melt a CPU by altering te voltage in the bios. :) (and no, I'm not planning on making that kind of a virus...)
13
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4answers
31k views

After Windows 8 installation I can't access BIOS settings anymore

Today I installed Windows 8 Consumer Preview on one of my notebook machines and I noticed that I can't access BIOS settings if I use the "Shut down" Windows option on Settings/Power menu. If I use the ...
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5answers
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How to know if my BIOS supports UEFI?

I recently bought a new Dell notebook for my girlfriend and I want to know if the computer comes with a UEFI BIOS, unfortunately I didnt find any information in the manual or on Windows, is there some ...
13
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Is there any way to boot Windows 7/8 using BIOS on GPT?

I'd like to know if there's a method to get Windows 7 or Windows 8 Developer Preview to install to a GPT disk on my traditional IBM PC BIOS setup. Windows 7, of course, rejects my GPT partition, ...
13
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3answers
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Change Linux Console's Default Monitor

Is there any way to specify which monitor the console is displayed on in Linux? Details: I have a 3 monitor setup with 2 video cards. When I boot the computer, the BIOS displays on the PCI graphics ...
12
votes
1answer
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How do I boot my Samsung laptop from a CD/DVD?

I have a Samsung Series 3 laptop and want to boot from an Ubuntu Live CD. When I press F10 to pull up the BIOS/boot configuration, I don't get an option to boot from the CD. Similarly, in the BIOS, ...
12
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5answers
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Bypass BIOS password set by faulty Toshiba firmware on Satellite A55-S1065 laptop?

I want to rescue this 7 year old laptop that has been crippled by a glitch in its BIOS: 'A "Password =" prompt may be displayed when the computer is turned on, even though no power-on password has ...
11
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11answers
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Switch on the computer automatically

Is there any way to switch on the computer automatically at a specific time. Is there any BIOS clock trigger mechanisms available to switch on automatically. EDIT: I have a Dell Inspiron laptop. Does ...
11
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4answers
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PC shutting down after 30 minutes, even when on BIOS screen

I have a desktop PC that is just over a year old that I use daily for work. It's running Windows 8.1, has 16GB RAM and an i7 CPU. It has a 256GB Samsung 840 SSD (Windows + programs) along with a 1TB ...
10
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4answers
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How to secure my Windows 7 PC?

Hi I am going on vacation. I wanna secure my PC. Is there any way I can lock down my PC so that nobody can boot up it? Any BIOS level security? BTW. I am running Windows 7 Ultimate.
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How can I change the BIOS serial number in VirtualBox?

VirtualBox sets the BIOS serial number of every VM instance to 0. It seems to be possible to change some BIOS settings, but I haven't seen anything that directly references the serial number. Can ...
10
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5answers
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Why is Intel Turbo Boost Not Working On My Laptop?

Investigation continued Why is Intel Turbo Boost Not Working On My Laptop? (Continued) Dell Latitude E6420 is my laptop with Windows 7 Enterprise. Turbo Boost is enabled in BIOS but is disabled ...
10
votes
2answers
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How to get into BIOS when USB keyboard is not powered and have no PS/2 ports?

Just got a new Windows 7 PC (64-bit) with an Intel DH67CL motherboard. It's been working fine but I decided I wanted to try to get into the BIOS. Unfortunately I can't do it because my USB keyboard ...
10
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2answers
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How can I re-program/flash a backup of the bios?

I have some computers that have a particular bios setting that keeps everything running smoothly. The setting is not the default setting for the motherboard. So, when the CMOS battery dies, the ...
9
votes
4answers
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How can I use TrueCrypt under windows 8.1?

I know that TrueCrypt doesn't support windows 8 because some systems have UEFI enabled. It seems that if UEFI is disabled or Windows 8 is installed on an non UEFI system TrueCrypt just works fine in ...
9
votes
3answers
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How to tell if windows 7 installer boot in EFI or BIOS?

I have a windows 7 64bit installation USB. I want to know if the windows 7 installer has booted into EFI or BIOS mode. I googled and found a solution here ...
9
votes
1answer
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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 here. ...
9
votes
1answer
913 views

wake-up by the computer

some time ago(10 years back) I've read on PC Magazine that some mainboards have some settings which allow to a computer to open at a certain hour. I need to make my computer to wake me up in each ...
9
votes
1answer
472 views

What “TYPE” of harddrive is in my old 286

I have a very old(1989?) 80286 computer. I can tell it was a very good machine in it's day. It has a harddrive installed. I finally got a PS/2 to AT keyboard plug today and got it to boot. Now I ...
8
votes
6answers
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How to enable 4GB in my Windows 7 64 bit?

I have the following machine configuration: Intel Core 2 Duo E6300 1 x 2048 MBytes memory chip 2 x 1024 MBytes memory chip 1 x Radeon HD 4870 Motherboard : Gigabyte 945P-S3 Windows 7 RTM 64-bit In ...
8
votes
4answers
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Is BIOS considered an OS? [closed]

This question comes to mind when dealing with RAID arrays, but is not necessarily applicable to the subject. How is that the BIOS is able read from a hard drive to effectively load the OS, when ...
8
votes
2answers
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Is there something like a BIOS in Windows 8? [closed]

Is there something like a BIOS in Windows 8? How can I set up the boot device priority? My problem occurs when switching on my computer. It immediately goes to Windows 8 loading screen without ...
8
votes
4answers
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Will my computer be able to run Windows 8 without UEFI?

Will I be able to run windows 8 on my system, even though I am not using UEFI? Is there a work around if I don't want to use UEFI?
8
votes
4answers
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What happens when a computer starts?

I'm trying to understand what happens when a computer is turned on. How the computer works on startup, various initializations that take place, etc. For example, is the bootstrap loader the first ...
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4answers
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BIOS upgrade lowers CPU temperature

Setup I've got a system with an Asus P8Z68-V PRO motherboard and an Intel Core i7-2600K CPU running at stock speed (no overlocking) which I cool with a Noctua NH-U12P. On the heatsink I've got the ...
8
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1answer
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Where's the BIOS on an Intel Mac?

When I use my laptop, I have no trouble at all accessing the BIOS and changing things like the boot order. However I recently got an iMac and have found that not only do the usual keys not get me to ...
8
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2answers
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Do hard drives need a GUID partition table (GPT) to boot in UEFI mode?

Is EFI booting something hardware specific? I have a desktop motherboard with a UEFI Bios, but I can only boot from USB drives in "UEFI" mode. Both the DVD drive and the HDD's (a RAID 0 array) boot ...
8
votes
1answer
677 views

I have a modern 64-bit CPU. Does my BIOS still operate in 16-bit REAL mode?

Since it is still required to boot, I am wondering, on a x64/AMD64 64-bit system, does the BIOS still use 16-bit instructions? Also does it operate in REAL MODE?