My PC (laptop) are of these specs:
2 X 8 GB 2133GHz SODIMM DDR4
(no motherboard info available online)
I bought 2 X 16 GB 3200GHz SODIMM DDR4,
disconnected main power and battery,
remove 2 X 8 GB sticks,
installed 2 X 16 GB sticks,
reconnected battery and main power...