3 Things to Know About Running 2666 MHz RAM at 2400 MHz

Your CPU’s memory controller maxes out at 2400 MHz Even if you buy 2666 MHz RAM, the processor will automatically clock it down to 2400 MHz. The extra speed is simply unused.

Enable XMP in BIOS to reach 2400 MHz Without enabling XMP, your motherboard will default to a lower JEDEC speed, likely 2133 MHz. You’ll leave performance on the table if you skip this step.

Don’t pay extra for 2666 MHz RAM If 2666 MHz costs the same as 2400 MHz, buy it—it’s fine. If it costs more, buy 2400 MHz instead. You won’t notice any performance difference.