If you have seen a "Firmware Update Tool" popup on your desktop, do not worry as it is a legit update from ASUS. The latest BIOS version 302 by ASUS is to fix an issue with the GPU vBIOS that causes system instability.
The popup looks like this:
As ASUS wants this update to reach every laptop, you may even see the popup even if you have installed BIOS version 302. Of course, you cannot update your BIOS since you are already running the latest version
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