I should add that the PC does display anything when it it turned onhttps://www.asus.com/support/FAQ/1029959/
https://www.thewindowsclub.com/computer-beep-codes-list
UEFI AMI BIOS
1 long then 2 short is usually a memory error.
Please post your entire system spec including RAM model, and PSU make and model.
A problem with the RAM can still perfectly cause that problem and it quite commonly does so.I should add that the PC does display anything when it it turned on
Sapphire RX 460 2GBA problem with the RAM can still perfectly cause that problem and it quite commonly does so.
A PC cannot boot without functioning RAM, so if it can't detect the RAM, then it won't boot and show signal. It will just power up and then nothing.
What is your full system spec?