Don't mix CAS latency RAM.

It will probably work, but your system will run at the speed of the slower stick. Mixing different CAS latencies forces the motherboard to use the loosest timings across the board. That means you’re paying for faster RAM and getting slower performance. It’s especially annoying on a 16GB setup because you’re already at a common capacity—just buy a matching kit.

The real risk isn’t damage; it’s instability. You might get random crashes, blue screens, or the system refusing to boot. Even if it boots, memory overclocking profiles (XMP/DOCP) go out the window. You’ll have to manually tune timings, which is a headache for maybe 10% savings.

Just buy a matched pair. Two sticks from the same kit, same speed, same latency. Future You will thank you when the PC just works.