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Question A Question about Mixing RAM Kits with different CAS Latency

Jan 30, 2024
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So, this year I built my first custom PC for gaming/data science workloads with 64GB (2x32 GB) DDR5, specifically the low profile G.SKILL Trident Z5 Neo RGB with Cas timings of 32-38-38-96. recently, I ran into an issue where the relatively small LiDAR dataset of only 27.5 GB I was trying to work with would max out my computer's RAM and cause the program I was using to crash.

So, I thought I would just grab another kit of 64 GB, but when I went on Newegg I saw that they no longer sell the same RAM kit with Cas latency 32 timings, the only ones left in stock are the ones with Cas Latency 30 (30-40-40-96) timings. So, the question becomes, will mixing the different Cas latencies cause stability issues?

If not, great! If they do, then It's a bit more complicated. I looked around and this specific kit is now only found on Amazon, and they want to charge an extra $100.00 Canadian compared to Newegg. I could get the non-RGB variant, but then it kind of clashes with the rest of my build (I know, i know, shallow reason). They have the Intel XMP version in stock, but I'm pretty sure that mixing XMP and EXPO RAM kits are a no-go. Or I could bite the bullet and get 2 kits of 96GB (2x48GB) since my CPU (i7-14700K) can support up to 192GB RAM. (Though I just checked and apparently the 14700K only supports up to 2 channels of memory? Does that mean 2 dual channel kits, or only 2 sticks total?)

Otherwise, does anyone have any recommendations for good low profile RAM kits I might want to look into? Thanks.
 
Mixing RAM is always a crapshoot.
Might work, might fail. Might work a little bit.

And even buying the 'exact same' falls under "mixing".

Unless it came in the same box as a set....mixing.
 
"Matched" RAM means just that, the manufacturer has tested the parts as a set and they guarantee they will work as a set. Anything else, and you are the one testing and tweaking them to get them to work.
 
Ah, makes sense. So my options are to buy as close of a matched set as I can and hope they work, cause I'm not really much for overclocking aside from enabling EXPO/XMP, or getting a kit of 4 matched sticks instead. Kind of wish I'd thought of this when I was doing the initial build back in March, but I thought that 64GB would be enough, and it is for most tasks, but when trying to deal with Big Data it falls just a little short.

Ah well, if I go with a kit of four I can at least save these old ones to use in a build down the road. Thanks for the answer you guys.