BIOS Settings

Booting into BIOS (or UEFI, as it’s now called) is the first step to configuring a new computer. It’s also confirmation that the core components are functional and capable of booting the system – always an encouraging step in the process.

As described in our “BIOS Overview”, the Basic Input/Output System has been more-or-less replaced by an elevated UEFI standard. Both reside on the firmware of the motherboard. UEFI and BIOS are accessed prior to boot and serve as a means of enabling, disabling, and controlling devices and controllers on the motherboard. In this regard, BIOS and UEFI are incredibly important; without them, we have no means of managing our components. The UEFI menu is also where CPU overclocking, memory clocks and timings, boot order, and the system clock are managed. All of this information is stored to a battery on the motherboard, called the CMOS battery (Complementary Metal-Oxide Semiconductor).

Getting Into BIOS

BIOS is easily accessed. Boot the system and keep eyes on the monitor – you should see some sort of splash screen (often with the motherboard maker’s logo) appear. At the bottom of the splash screen will be listed keys. Almost every motherboard uses the ‘del’ key to get into BIOS, but some (particularly laptop BIOS) will use F2, F11, or F12. Many motherboards also offer a temporary boot order menu; if changing boot order is all you want to do, look for that hotkey (usually F12 or F8).

Hit the key repeatedly while booting. UEFI / BIOS should open. If in doubt, use the delete key.

BIOS Settings
BIOS Settings

First Things First: Boot Order

The most commonly configured BIOS item is probably boot order – or the priority by which devices are checked for bootable media. Installing via CD or USB, for instance, would mandate that the boot order elevates these items to the top of the boot order list. Pre-UEFI, BIOS had to be controlled entirely by the keyboard, but mouse control has been added with UEFI (as have higher bit graphics and elevated controls which speak to the OS/Host). Use your preferred input device to tab over to the ‘boot’ page.

Arrow keys and tab will perform navigation functions (or use the mouse); enter will open deeper menus for selected items.

Once here, you’re likely offered a few key options – one of them will be the Boot Mode, listed as either UEFI or Legacy. Because this is a brand new system, we’re going to do it right and opt for UEFI boot mode – that’ll grant more control in the future, particularly when it comes to the possibility of multi-boot systems.

Next, you’ll see bootable items listed in descending order of importance. Configure the top boot item to be your install media – either an optical drive or USB key – and the second item as your SSD or hard drive. We will change the first boot item to the primary drive post-install.

Note: Some UEFI tools do not represent boot order as a list activated with the enter key, but instead use a click-and-drag interface with visual cues. The click-and-drag style is common with MSI motherboards and often is visible toward the top-center of the interface. Hover over the images to determine which is the bootable media, then drag that item to the left (first boot item).

Don’t Install the OS Just Yet

Don’t reboot and begin the install yet. Next, we need to make sure the SATA mode is configured to the mode appropriate for your device. This step will ensure that the host drive operates to its fullest potential, rather than using a SATA mode which may be slower or inappropriate for a particular SSD or HDD.

This is normally under the ‘advanced’ tab, then within a menu item named something like “SATA mode,” “AHCI,” “RAID,” “NVMe,” or similar.

For a somewhat standard 2.5” SSD or 3.5” HDD, it’s best to select AHCI mode. This is in opposition to, say, Legacy IDE mode – you don’t want that unless using a decade-old HDD with an IDE ribbon cable (those gray ribbon cables that predated the SATA interface).

For RAID installs, the obvious choice is the “RAID” mode. This is used for multi-disk RAID configurations. Additional RAID management will be required to properly inform the motherboard of the preferred RAID mode (e.g. RAID 0, 1, 5, 10). This is done outside of BIOS, but pre-boot, and is normally accessed through a ctrl+s hotkey. The manual will inform you of the correct input.

And then there’s NVMe – this one’s getting more popular. Devices on the market with NVMe support will communicate via the PCIe interface, tapping into more lanes and offering greater transfer speeds than capable through the SATA interface. You likely know if your SSD supports NVMe, as it’d be blazoned all over the box. Intel’s 750 Series SSDs, for instance, are NVMe enabled. These insert into the PCIe slot. Not all PCIe SSDs use NVMe. Some of them will use the SATA interface, but are adapted from PCIe using an adapter card.

Memory Speed & Timings

If your memory uses XMP (eXtreme Memory Profile) or has other built-in profiles, tabbing over to the memory tab will allow configuration of these speeds. It used to be the case that chipsets would run all memory at a maximum of 1333MHz or 1600MHz by default, but that’s changed in modern days – an “auto mode” allows UEFI to semi-intelligently select the correct speed for the RAM it detects.

But it’s not always correct, and that’s where manual configuration comes in.

Navigate to the tab that includes memory speed and timings. This is either on its own page (“Memory”) or as part of the “Overclocking” page, should your firmware offer such a tab.

Locate Memory Speed. You’ll want to set this to be equal to your RAM’s advertised speeds. We can worry about overclocking at a future data – for now, just go with the built-in profile as those are fairly guaranteed to work (but do sometimes have trouble, and that’s why there are often two profiles).


If this is a work system or will be deployed in an environment where security is demanded, some UEFI menus will allow the configuration of an administrator password. This password will usually (read the manual – sometimes this is implemented via TPM, Trusted Platform Module, or advanced means) block access to UEFI without the password. This restriction is useful as UEFI can easily be exploited – like changing boot order to prioritize a USB key with malicious software – and should be used for any public-facing computer.

Can I Overclock Now?

We’ll get to overclocking in a future guide. For now, it’s not yet time. A basic install needs to be configured first, including Windows and OC tools, so that we may properly validate overclocks and check for stability.

Resetting BIOS If Something Doesn’t Work

If some of the newly-applied settings prevent boot or trigger failures, toggle power to the PSU and pull the CMOS battery to instantly clear BIOS and start from scratch. – Steve Burke, GamersNexus