Need to change your PC’s boot order or set a password? Here’s how to access and use the BIOS, and some commonly changed settings.
Older desktop and laptop computers have a hidden software feature called BIOS. Making them can improve the way your computer works.
What is BIOS?
The BIOS (basic input/output system) lives on a replaceable or upgradeable chip. This is low-level software that starts when you boot your computer. It performs a POST (power-on self-test), initializes your hardware, and passes control to the boot loader on the connected device. This then boots your operating system — Windows, Linux, or whatever you’re using.
All of this is automatic, but the BIOS also has a setup screen, which you can access. Used to configure various low-level system settings, you can use it to manage things like:
- Boot order
- Video memory
- Power management
- Fan management
- And moreâ€¦
Note that you shouldn’t change any settings in the BIOS unless you know what you’re doing. One wrong step and you can change low-level CPU and memory settings which can make your computer unstable.
So make sure you are familiar with or familiar with your computer’s BIOS before saving any changes. Keep reading to see our tips for changing some of your most used settings.
NOTE: This guide is specifically about BIOS. However, since 2010 BIOS has been gradually replaced by UEFI.
To access the BIOS, restart your computer first. Press the appropriate key at the start of the boot-up process to access the BIOS setup screen. The key you need to press will appear on the screen at the start of the boot process. Note that if no keyboard is attached to your PC, you cannot access the BIOS.
This is usually the Delete key, although some computers may use other keys such as F2, Esc (ape), F1< /b>, or F10. If you don’t know which key you need to press and it doesn’t appear on the screen, consult your computer manual. Alternatively, do a Google search for your computer’s model name and “BIOS key”.
Navigating the BIOS
Note that each computer’s BIOS is different. Your computer’s BIOS may look very different from the screenshots here, or it may look similar but have different options.
To navigate the BIOS, use the arrow keys on your keyboard. A list of other keys that you need to use usually appears on the screen. Usually, you would use:
- Left and right arrow keys to switch between settings screens
- Up and down arrow keys to select an option on the current screen
- Enter to select an option or enter a sub-menu
- Button + and — to move items up and down in the list
If this sounds a bit complicated, it really isn’t — you’ll mostly be using arrow keys and Enter.
3 Most Common Settings Changed in BIOS
With access to the BIOS, you’ll find settings you should ignore — as well as some that might need to be changed. The most common BIOS settings for modification are:
- Change boot order
- Adjust available video memory
- Setting a BIOS password
Here’s how to do each of these.
1. Boot Order
One of the most changed options in a computer’s BIOS is the boot order.
After the BIOS starts and initializes your hardware, it passes control over to the boot loader that boots your operating system. The boot order determines which devices the BIOS gives control over.
For example, you install Windows on your computer and a Linux live CD on your disk drive. (Or, a USB drive is plugged into your computer.) When you boot your computer, which operating system starts? The answer is determined by your boot order.
So called because it controls the order in which the boot device checks for the OS. For example, a typical computer might have a DVD drive higher in the boot order list than an HDD. This means the computer will try to boot the operating system installation disc or live CD that was inserted first.
If there is no bootable disc in the DVD drive, the computer will try the next option on the list. This will most likely be the hard drive. You can boot your PC from:
- Optical drive (CD, DVD, Blu-ray, etc.)
- USB drives (hard disks, thumb drives, or even USB optical drives)
- Network DriveÂ
If you want to boot another boot device, simply move it up in the boot order list. Usually you’ll find the boot order on the screen called Boot or something similar. Use the + and — keys to reset the device in the boot order list.
Note: on some computers, the USB drive may not appear in the list unless the USB drive is connected when you enter the BIOS.
2. Video Memory
Computers with onboard graphics hardware, such as Intel integrated graphics, may have a Video Memory setting. The onboard graphics hardware does not have its own memory the way a dedicated graphics card does. Instead, it takes over a portion of the computer’s RAM and uses it as its video memory.
On some computers, the Video Memory option allows you to control how this memory is allocated. You can use this to allocate additional video memory or reduce it, reclaiming some of it for system tasks.
3. BIOS Password
While your operating system must have a login password, you can further secure your computer with a BIOS password.
This can be set to control access to the BIOS; however, you can also set a boot password. With this enabled, no one can access the operating system or installed media.
Be aware that this is not a perfect security feature. Anyone with physical access to your computer can reset the CMOS to clear this password.
What does Save Changes and Reset in BIOS do?Â
Your changes to the BIOS settings will not take effect immediately. To save changes, look for the Save Changes and Reset options on the Save & Exit . This option saves your changes then resets your computer.
There is also a Discard Changes and Exit option. This is for if you make a mistake or decide you don’t want to change your BIOS settings at all. Just use this option to exit the BIOS setup screen without saving your changes.
(This option may have a slightly different name, but is available in all BIOSes.)
You can also use the appropriate keyboard shortcuts to quickly save and exit. Often this is F10 but again, it may be different in your BIOS.
What Happens When You Load Default Settings?
Your BIOS also contains Load Setup Defaults or Load Optimized Defaults options This option resets your BIOS to factory default settings, loading default settings optimized for your hardware.
Fix errors in BIOS by loading default settings
This performs a complete BIOS reset, removing any BIOS passwords other than resetting your hardware settings and boot order.
You probably won’t be using this, but it can be useful for quickly changing configurations after adding new hardware.
Other Less Common Settings Changed in BIOS
The BIOS contains several other settings and options.
For example, there is a System Information screen that displays information about the hardware on your computer. Overclockers may be able to use the CPU settings screen to change their CPU voltage and multiplier. This increases CPU performance at the cost of additional heat, power usage, and possible instability. (However, some BIOSes lock this setting.)
Meanwhile, if your PC has support for virtualization, you can enable Hyper-V or Intel Virtualization Technology (or however it’s labeled) in the BIOS.
For a full selection of settings that you can modify in the BIOS, check your computer or motherboard manual.
Use BIOS to Optimize Your PC Settings
You should now be familiar enough with your computer’s BIOS to make some minor changes.
But it’s important to know that you shouldn’t change settings unless you know what you’re doing. Simple changes include adjusting the boot order or video memory and if you get an error the default settings will help.
Remember to make your BIOS choices carefully. Getting the BIOS settings wrong can cause problems. It’s one of the few PC maintenance mistakes you can make.