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How To Update BIOS without CPU

One of the most unfortunate things to happen after building your PC is your motherboard not booting. If this happens, you’ll need to update the BIOS. But how exactly do you update BIOS without CPU?

Isn’t the point of turning on your PC the first time is to make sure that everything’s working? Well, don’t worry. In this article, we’ll show you how to update BIOS without CPU and other tricks you’ll need in the future.

Aorus Motherboard Update BIOS without CPU

What Exactly Is a BIOS Flashback?

BIOS flashback is a common feature found in motherboards that allows you to update your PC’s BIOS without installing memory, GPU, or even a CPU.

Depending on the brand of motherboard, flashback is referred to as the following:

  1. Gigabyte motherboards call it Q-Flash Plus (not the same as Q-Flash, which is the software used to update the firmware from within the BIOS).
  2. MSI motherboards call it Flash BIOS Button (not the same as M-Flash, MSI’s update utility).
  3. ASRock motherboards call it BIOS Flashback Button.
  4. ASUS motherboards call it USB BIOS Flashback

If you want to know if a motherboard has a BIOS flashback, you’ll need to check the manufacturer’s sheet or the website itself. On the spec sheet, it will appear as the name as it’s listed on here.

What If Your Motherboard Does Not Have BIOS Flashback Feature?

On the off chance that your motherboard does not have a flashback feature, don’t worry. There’s still something that you can do. First, you need to acquire a fresh and formatted FAT32 USB flash drive.

What Do You Need a FAT32 USB Flash Drive For?

A FAT32 USB flash drive is what you need to boot up your motherboard’s BIOS without a CPU. Now, users flocked to Reddit citing that new USB 3.0 drives have certain issues when it comes to doing BIOS flashback updates. This is not guaranteed for everyone, but to be on the safe side, just use a USB 2.0 flash drive when possible.

BIOS software and updates are relatively small, so you’d only need a USB flash drive that’s about 16GB or smaller. But the main reason why you shouldn’t use larger flash drives is that older motherboards may have problems detecting them.

How Do You Update BIOS Without CPU or Do BIOS Flashback?

Check your Motherboard’s Official Website

Download the BIOS update file from the motherboard’s manufacturer website using another laptop or desktop. Never download any BIOS files outside of official manufacturer websites.

Do a quick search for your motherboard model on Google and it should take you to the official manufacturer’s page for that model.

Download the BIOS Update

Once you’re on the motherboard’s official page, click on Support tab (or its equivalent), then go to the BIOS section. This is usually found under Drive and Utilities.

You should see different BIOS versions alongside their release dates, but the more recent updates are located at the top of the list. Always download the latest BIOS version when you have to.

However, if the latest BIOS version has something with “BETA” affixed to it, don’t download that version if it’s only less than a week old. If not, then just download that version still.

Extract Download and Rename BIOS File

After downloading the file, extract the file first and then rename the BIOS file.

If you have an ASUS motherboard, it should come with a BIOSRenamer.exe utility. Just double click that and it will automatically rename the file. For MSI, Gigabyte, and ASRock motherboards, you’ll need to rename the file by yourself. Just look for the BIOS file, which should be the file with the largest file size in the folder.

Then rename them by following these formats:

  • If you have a Gigabyte motherboard: rename the file to gigabyte.bin
  • If you have an MSI motherboard: rename the file to msi.rom
  • If you have an ASRock motherboard: rename the file to creative.rom

You’ll get a warning prompt saying that renaming might make the file unstable. Click Yes because this is a normal message prompt after renaming. It doesn’t matter if you use uppercase letters or lowercase letters as Windows reads them the same.

Format USB Drive as FAT32 and Transfer BIOS File

Plug the USB flash drive in and open My Computer or My PC (Windows 10/11). Right click on the drive and click Format. Select the FAT32 option and not NTFS.

If you recently formatted a flash drive but unsure of whether or not it’s FAT32, just right click on it and select Properties.

Copy the BIOS file (the one that you renamed) into the main directory or root of the USB flash drive.

Eject USB Drive from the PC You’re Using and Connect Power Supply To Your Motherboard

Eject your USB flash drive from the PC properly.

On the motherboard that you’re planning to update the BIOS, connect the power supply. But before you plug it into the wall, make sure that you connect the large 24-pin main motherboard power connector and 8-pin CPU power connector.

Yes, you’ll need to connect the CPU cable to the power supply even if you don’t have a CPU installed on there. Once all the cables are connected, plug the power supply to the main socket.

Insert USB Drive and Press Flash BIOS Button

Flash BIOS Button Update BIOS without CPU

Remember, for this part, you don’t need any other parts mentioned on your motherboard other than the ones mentioned in the previous paragraph.

Insert your USB on the special USB port behind the motherboard. This special port is labeled as BIOS or some equivalent.

IMPORTANT: make sure that the power supply is turned on BEFORE inserting the flash drive. Some people have done the reverse and faced several issues. Manufacturers will also tell you to turn the power on before inserting the flash drive.

Once the flash drive is inserted, locate the small BIOS flash button somewhere next to the USB port on your motherboard and press it. Some motherboards will have it on the actual board and not behind the motherboard. For Gigabyte motherboards, the button will be labelled as Q-Flash Plus.

On some motherboards, like ASRock, you’ll need to hold down the button for three seconds. If your motherboard is MSI or Gigabyte, you’ll need to press down the button for three seconds if nothing happens the first time you pressed it.

If done correctly, the firmware will update itself with the BIOS file installed on the USB drive. This shouldn’t take you long but just make sure that there’s no power interruption as you’re updating.

When the update is complete, the LED light will stop flashing and the motherboard will either restart or shut itself off.

You can now remove the USB drive, turn off the power supply, and proceed to install all the remaining parts (i.e. CPU, GPU, and so on).

The Wrap Up

Now you know how to update BIOS without a CPU. It’s worth mentioning that there’s no actual need to update your BIOS unless you absolutely have to.

James Stephenson

james stephenson profile picJames is a gaming and tech enthusiast. He has been playing computer games since the Commodore 64 days in the 80s. He has worked as a Broadcast Engineer with BBC News and knows a thing or two about building, fixing, and playing with PCs.