In this post we are going to touch on a topic that is often asked a lot in the forums. What to do if I can't get into the BIOS? Being able to do this is essential, for example, to change the boot order of installed operating systems or the read priority of storage devices.
To save you reading time, I'll start by saying that the problem is probably that we're pressing the wrong key. Although the usual is the key above, some notebook models chose to assign that task to some of the function keys.
If you know what the BIOS is and why enter it, in the next section I explain some things you can do to enter it. If you have no idea about either, in the second section I explain the basics.
I can't get into the BIOS. What do I do?
Now that we know that the secret is to hit the right key, the next question is know which one to press. I am going to mention some of the possible alternatives. If they do not work, you will have to go to Google and indicate the model of your motherboard.
To access the BIOS we can press any of the following keys or key combinations:
- F1
- F2
- F10
- Delete (On English keyboards it can appear asFrom o Delete)
- I
The capital F identifies the function keys located on the first row of the keyboard. Whichever is indicated, it must be pressed during the boot process.
There are certain clues that make it easier for us to find the function keys. In some cases a sign indicates which is the indicated key. In case it doesn't:
- yes when you press F2 A diagnostic tool appears, try restarting and pressing F10.
- If you decided to start with the highest function key (F10) and the disk list and its boot order appear, restart and press F2.
It's almost a no-brainer to say, but you won't be able to enter the BIOS if you don't have a keyboard. Old computers wouldn't even boot if you didn't have it plugged in. Although the new ones will start the operating system with which you will be able to use a virtual keyboard, and, the new versions of the BIOS allow changing the settings using the mouse, without a physical keyboard any modification is impossible.
Restoring factory settings
When the other methods of accessing the BIOS do not work, you have to work on the Motherboard to restore the factory settings.
This is what the old Reader's Digest magazine called "Real Life Drama." In other words, it happened to me and it took me 4 months working with borrowed computers.
My equipment stopped working. I changed the power supply and it still didn't do it, I changed the motherboard and it still didn't. Finally I changed the processor and it would boot, but it would show no video. Why I didn't take it from the beginning to a technical service to diagnose the problem is a story that will be left for another time.
What happened was that, Despite the fact that the motherboard website claimed that it was compatible with the processor, the BIOS version was not compatible. Had to download an older version for it to work.
Another problem that you can run into, and that is solved in the same way, is when access to the configuration options is protected by a password and you do not know it.
What to do is restore to factory settings and this is done by intervening in the hardware. This must be done by specialized personnel because things can go really wrong.
desktop computers
On the motherboard we must find a DIP switch or jumper labeled as CLEAR JCMOS1 CLEAR CMOS, CLRPWD, CLR, PASSWD, PASSWORD, PSWD or PWD. We only have to change the position of the switch or remove the jumper from the two connecting pins and place it on the two remaining jumpers.
Some possible locations are:
- On one of the edges of the motherboard.
- In the immediate vicinity of the battery.
- In the immediate vicinity of the CPU.
Another method is to remove the battery from the CMOS chip for 5 minutes.
Laptops
In the case of laptops, it is best to contact the manufacturer and ask you what the default password is or ask you to reset it. The latter will only be possible if you are the original purchaser.
Another thing you can try is run a script that can generate the password from certain clues. For this we must first access the BIOS and type a wrong password three times. Scripts must be run on another computer
What are we doing this for?
When assigning a password to the BIOS, the system stores a checksum in the CMOS chip, that checksum is the one that is displayed in the message that appears after three failed login attempts. Other manufacturers prefer to display a number. In the first case it is possible to obtain the original password, in the second a master password made up of randomly generated numbers.
Other variants include storing the password in plain text, but encrypting it before displaying it. while they generate a master password from the serial number.
It must be said that not in all cases it is so easy. Some computers require you to enter three passwords before you can see the checksum, or only display it if the keys are pressed in the correct order.
The scripts can be downloaded from this page. To run them on Linux you must download them, open the terminal and go to the download directory. Then you start it with the command python name_of_script.py
In case this doesn't work, you can try the same method as on desktop computers. The first place to look is under the keyboard.
BIOS Basics
The BIOS is a special type of software stored on a chip attached to a battery. If the battery dies, when the computer is turned off, the configuration information will be lost.
In this section we will answer two questions:
What is BIOS?
The fundamental component of any computer is the motherboard. Its function is to interconnect all the components of the computer. On the motherboard we find a chip known as CMOS (Acronym for complementary metal oxide semiconductors)
CMOS acts as volatile storage memory for a firmware known as BIOS. We say that it is a volatile memory because in the event that the power supply is cut off, its content is lost. That is why CMOS has its independent power supply from the mains (its own battery). Even if the computer is not connected and even if the motherboard has never been connected to a computer, CMOS is ready to use with factory settings. Or, with the modifications that we make later in the configuration.
In the event that the 3-volt battery that acts as the power source for the CMOS chip dies, settings (either factory or user-modified) will be lost. and we must adjust it every time we disconnect the computer and turn it back on.
I said before that BIOS is a firmware. This is a computer program that is integrated into a hardware component and whose role is to allow its operation. BIOS is in charge of making sure that the computer is in optimal operating conditions.. Once this is done, it passes the message to the bootloader of the operating system.
When the computer is disconnected from the mains, the CMOS chip draws power from a battery that must be replaced when it runs out.
The name BIOS comes from the acronym in English for Basic Input and Output System and deals with the configuration of the components of the computer.
BIOS has four main components:
- POST: It is in charge of verifying that the different hardware components work correctly, if they do not, it reports the type of error through beeps.
- Bootstrap Loader: It looks for a bootable operating system and hands over control to it.
- BIOS Drivers: Set of software in charge of managing at a basic level the different hardware components.
- Setup Wizard: It allows you to configure different aspects of the hardware such as the boot order of the storage media or the system date and time.
I'm going to tell you a secret. I recently took a computer repair course. In my case it was to learn how to repair my own equipment, but the course is part of a job training program supported (and paid for) by the Argentine Ministry of Labor.
To write this article I wanted to refer to the course notes and, as an additional measure, I compared what it said with the BIOS of my own computer. The bottom line is that the professor was at least 20 years out of date.
My advice is that if you decide to mess with the BIOS setup or other hardware, search for updated information and compare everything you see or read with what you see on your computer. Also, before making changes, take notes and document them with photos and videos.