Even if you install 3200 MHz RAM, it'll simply downclock. The CPU controls the memory bus speed -- and that cannot be upgraded.  
Hi there, I had a Dell G3 3579 i7 with 1060 max q. I would like to ask is the laptop supports 3200mhz ram or is it capped at 2666mhz? I had saw a compatible list for 3579 at crucial which mentions that 3200mhz RAM is supported meanwhile Dell hardware manual only mentions the 2666mhz RAM.  Crucial website i found: [URL]
Dell G3 3579 RAM speed support