If you’ve built a PC desktop in the last few years, you’ve probably been exposed to the confusing array of DDR4 information when it comes to buying RAM.

What it comes down to is not all RAM is created equal. Once you get past pin size and memory capacity, you’ll have to filter down by speed. Speed isn’t a simple one-figure number — you may see a rated speed like 2400MHz, but you may also see another bunch of numbers like 16–16–16–39 indicating the necessary clock cycles to perform certain types of memory operations.