How to update the BIOS on an Asus laptop safely
When a BIOS update is worth doing, the three ways to do it on an Asus laptop, and the precautions that stop it going wrong.
The BIOS (on modern laptops, strictly the UEFI firmware) is the small program that starts your Asus laptop before Windows loads. Asus releases updates for it to fix bugs, improve stability and battery behaviour, support newer parts and close security holes. Updating it is usually straightforward, but it is one of the few jobs where an interruption can leave a laptop that will not start at all. This guide explains when an update is worth doing, the three ways to do it on an Asus laptop, and the precautions that matter.
Should you update the BIOS at all?
A BIOS update is not routine maintenance in the way Windows updates are. A good rule is: update when there is a reason to.
- Good reasons: the release notes on Asus's support page mention a problem you actually have (for example random shutdowns, a fan behaving oddly, a battery not charging fully, a dock or monitor not being detected), Asus lists it as a security update, or a technician has asked you to update it while diagnosing a fault.
- Weaker reasons: the laptop works perfectly and the update only adds support for hardware you don't use.
- Don't update while the laptop is unstable for another reason, such as shutting down randomly from overheating or a failing battery. An unexpected power loss mid-update is the main way a BIOS update goes wrong.
Always get the update for your exact model. Asus model names such as "Zenbook 14" cover several different motherboards, so use the full model code (for example UX3402ZA or GA402RJ), which is printed on the label underneath the laptop and shown in the MyASUS app.
Before you start
- Plug in the charger and make sure the battery is reasonably charged as well. Many Asus updates refuse to run below a set charge level, and that is a sensible safeguard.
- Back up anything important. A BIOS update does not touch your files, but if something does go wrong you want them safe.
- Suspend BitLocker if your drive is encrypted. Many Windows 11 laptops encrypt the drive automatically. A firmware update changes the measurements the security chip checks at start-up, and Windows may then ask for the 48-digit BitLocker recovery key. To avoid this, open Control Panel, choose BitLocker Drive Encryption and select "Suspend protection" before updating; it resumes after the next restarts. It is also worth checking that you know where your recovery key is (usually in your Microsoft account).
- Close other programs and disconnect docks and external drives you don't need.
Method 1: MyASUS (easiest)
Most current Asus laptops come with the MyASUS app. Open it, go to the system update section (named "System Update" or "Customer Support" then "Live Update", depending on the version) and look for a BIOS entry. MyASUS only offers updates intended for your model, which removes the risk of choosing the wrong file. Start the update, let the laptop restart, and leave it alone: the screen may go dark or show a progress bar for several minutes, and the fans may run loudly. Do not close the lid or press the power button.
Method 2: Asus's Windows BIOS installer
On the support page for your model, under BIOS and firmware, Asus usually provides a Windows installer for the BIOS (sometimes called the BIOS Update for Windows or Winflash package). Download it, read the notes, run it and follow the prompts. It does the same job as MyASUS but lets you choose the version and read exactly what it changes.
Method 3: EZ Flash from a USB stick
If Windows won't start, or you prefer not to flash from inside Windows, the BIOS has its own updater, EZ Flash.
- Download the BIOS file for your model from Asus's support page and extract it onto a USB stick formatted as FAT32.
- Restart the laptop and press F2 repeatedly as it starts to enter the BIOS setup.
- If you see the simple screen, press F7 for Advanced Mode, then open the Advanced tab (or the Tool menu on some models) and choose ASUS EZ Flash.
- Select the USB stick and the BIOS file, confirm, and wait for the laptop to finish and restart.
EZ Flash checks that the file matches your model and won't install a file meant for another one, which makes it a safe fallback.
After the update
The first start can take longer than usual and the screen may flicker or restart once or twice. That is normal. Once Windows is running, check that BitLocker protection has resumed and that anything you had problems with is now behaving. If you changed BIOS settings in the past (for example the boot order or virtualisation), check them again, as some updates reset settings to their defaults.
When it goes wrong
If the laptop shows no picture after an update, give it time first: leave it on charge for 20 minutes, then hold the power button for around 30 seconds to force it off and start it again. Some Asus models can recover a damaged BIOS automatically on the next start. If it still shows nothing, or sticks on the Asus logo, see our guide to an Asus laptop stuck on the logo. A BIOS chip that has been left corrupted by an interrupted update can often be reprogrammed with specialist equipment, so a failed update doesn't automatically mean a new motherboard.
Not sure whether an update is the cause of your problem, or whether you should apply one at all? Our Asus help guides cover the most common faults, and if the laptop won't start, read how to fix an Asus laptop that won't turn on. You can also call us on 020 7394 2525 or ask for a free quote, and tell us the model and what happened.