Is 2666 MHZ RAM backward compatible with 2133 MHZ RAM and sockets?

Question

https://www.dell.com/support/kbdoc/en-us/000132025/dell-latitude-memory-compatibility-guide specifies that Dell Latitude 7480 expects 2133 MHZ RAM.

Nowadays it is barely accessible and more expensive than say 2666 MHZ RAM.

Would 2666 MHZ RAM work in this laptop?

I already have single working RAM piece, 2133 MHZ one. Is it fine to buy single 2666 MHZ RAM piece to insert into the second socket? Or should I change both to avoid different RAMs partially or completely incompatible with each other?

Answer 1

There is no problem 7nder driving ram. The speed specified is the maximum speed that it works reliably at. So 2666MHz ram will work fine instead of 2133MHz one.

If you are mixing them then they should be of the same architecture. Your best guide is yhe motherboard manual.