Asus Mini PC PN41 Manuel De L'utilisateur page 34

Installing memory modules
Your Mini PC comes with two SO-DIMM memory slots that allow you to
install two DDR4 SO-DIMMs.
Align and insert the memory module into the slot (A) and press it down (B)
until it is securely seated in place. Repeat the same steps to install the other
memory module.
IMPORTANT! Refer to http://www.asus.com for the list of compatible
DIMMs. You can only install DDR4 SO-DIMMs to the Mini PC's DIMM
slots.
34 PN Series