Question Does RAM added to second empty slot have to be exact as original in first slot?

[SoDifficult]

I have a Dell XPS 15 (9550) with manufacture installed "16GB DDR4 at 2133MHz - 1 DIMM" in slot 1.

Slot 2 is empty.

Can I add "Crucial 16GB DDR4-2400 SODIMM" to slot 2, making it 32GB, or do I have to buy two of these so each RAM is identical?

Is there anything else I should be considering or concerned about?

Thanks!

 

[USAFRet]

Not just "the exact same", but rather "bought as a single set" to guarantee functionality.

If you want 32GB, buy a 32GB set (2x 16GB).

 

[Jason H.]

I have a Dell XPS 15 (9550) with manufacture installed "16GB DDR4 at 2133MHz - 1 DIMM" in slot 1.

Slot 2 is empty.

Can I add "Crucial 16GB DDR4-2400 SODIMM" to slot 2, making it 32GB, or do I have to buy two of these so each RAM is identical?

Is there anything else I should be considering or concerned about?

Thanks!

1st of all, RAM that is NOT bought as a kit is never GUARENTEED to work together. With that said, if you add a faster stick of ram (the 2400mhz stick) to a slower stick of RAM in dual channel, the pair will run at the speed of the slower ram. Of course some people are good enough to overclock the slower stick to match the faster stick but that does NOT always work.

IMO I wouldnt do it. I mean if you add it, and it works fine after some Memtest, and your fine with the slower speed, by all means go ahead, WHY NOT RIGHT?

But RAM kits have came down in price so much lately that you can buy a 32gb kit for like 150 bucks of 3200mhz ram that is guarenteed to be faster, and work together properly with no bullcrap.

Or try buying a 2nd identical stick (same model number) and throw that in. Be like 40-50$. You would have much better luck doing that than throwing a entirely different stick in, But even then it wouldnt be guarenteed that it would work, but most of the time it does.