CAS Latency

[Peelingspud]

What would the performance difference between a CAS latency of 15 v 22 ?

I have an Asus Strix ROG Z270E motherboard and the current ram installed is Kingston HyperX Fury 2x8GB Dual channel (16GB total ) part number HX426C15FBK2/16 DDR4- 2666 CL15 and I am upgrading it to Crucial Pro 32GB Kit (2x16GB) DDR4-3200 • CL=22 • Non-ECC • UDIMM CP2K16G4DFRA32A as Crucial shows that memory is compatible with my system.
I have ordered the one Crucial kit for now to see if it works okay before getting another kit.

I was thinking it would not be a good idea to mix the current ram with the new ram as it's a different manufacturer and different size memory.

[Peelingspud]

Oprindeligt skrevet af 尺．し工几句ヨ尺:

Oprindeligt skrevet af Peelingspud:

Sorry but I don't understand what you are saying here.

With higher DRAM frequency, it's easier for the RAM to run lower timings.

CAS Latency itself doesn't matter as a stat, the subtimings do more than the primary timings.

https://www.youtube.com/watch?v=pgb8N23tsfA

Thanks for that !

[Peelingspud]

Oprindeligt skrevet af nullable:

There is an argument that if the first number is bad, the sub timings aren't going to be amazing either. And sure the sub timings for something that's CL16 could be different between two different models of RAM and one could be better than the other. So I would look at the sub timings too, personally, but generally I'd also wager the sub timings on something like 3200mhz DDR4 CL16 are going to be better than the sub timings on 3200mhz DDR4 CL22.

Overall I'm not that fussed about it, CL is just another data point long with speed, that can tell you a bit about the expected performance. Sometimes you might care more for your finely tuned custom built machine, so the details are important. And you might not care so much for your random aging prebuilt, because you don't care about the RAM in it now, and RAM is gonna be good enough.

There's a spectrum of concern I'd say.

I have the ram now so it is what it is and I'll work on overclocking if needed. The price seemed expensive, $240cad, but compared to when I bought it at $212cad for 16GB it doesn't seem so bad :-) !

Thanks again for all the useful info, very informative. I used to do a lot of computer builds by myself since the first PC came out, previous to that I used Commodore 64 and Amiga's, but now it's a lot different and hard to keep up at my age (77) !
Have a nice day :-)