Do not search for a downloadable EXE. Search for your motherboard model + "BIOS" on the ASUS website.
The USB flash drive must be formatted to a with a single partition . It is recommended to use a USB drive with a capacity of 1GB or more for this process. If your drive uses a different file system like NTFS or exFAT, the motherboard's built-in ASUS EZ Flash utility will likely not recognize it. download asus ez flash utility
During the first boot after a BIOS flash, your PC may turn on and off 2 or 3 times sequentially. This is normal behavior as the motherboard trains the memory and adapts to the new firmware. Do not search for a downloadable EXE
Optional: If your download includes a tool called BIOSRenamer.exe , run it inside the USB folder. It automatically converts the file name to the proper format required by some ASUS motherboards. How to Use ASUS EZ Flash 3 (The Update Process) It is recommended to use a USB drive