ram in wrong slots
The right way to put RAM in your PC's memory sockets | PCWorld
Sounds like you have either the wrong RAM module (spec) or the systems firmware is not up to date (I would be surprised if it's not already at the correct level).
Games Crashing After Installing New RAM: Fix it in 5 Steps
This setup was not always possible in older computers, and the computer would not boot if the user plugged RAM into the wrong slot.
Hướng dẫn kiểm tra thông số RAM bằng CPU-Z
Curious about your computer's RAM slots? Learn how to use CPU-Z, the ultimate hardware monitoring tool, to uncover the number of RAM slots in your system. In...