DDR4 CL14 and CL15 Question

Deight

Junior Member
Jun 29, 2018
3
1
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Hello to all, I'm new to the forum, and I'm really into pc tech, but I've never touched the ram part, so I have a question for you, and be glad if you can help me.

I have Kingston HyperX Fury DDR4-2133 CL14 288-Pin DIMM
( https://www.kingston.com/datasheets/HX421C14FB_8.pdf )

and I'm planning on buying HyperX Fury DDR4-2400 CL15 288-Pin DIMM, Kingston aswell
( https://www.kingston.com/datasheets/HX424C15FB2_8.pdf )

My worries are, will they be compatible if both are set to 2133 Mhz CL14 (or CL15) for a dual channel method, both are 8gb.

Mainly looking for this option, since my current same model ram is discontinued (at least in my country) and the new ram that I'm looking to buy as much as I'm aware, has a JEDEC profile that is the same (at first sight) as my current ram specs. Any ideas/advices are welcome. Thank you in advance
 

Shmee

Memory and Storage, Graphics Cards
Super Moderator
Sep 13, 2008
6,031
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It depends on how picky the motherboard and CPU are, but I suspect that if you leave them at stock JEDEC settings, they will work fine together. The BIOS will likely auto assign the timings. I would then memtest to be sure there are no errors.
 
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Billb2

Diamond Member
Mar 25, 2005
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Motherboards read the SPD table in the memory stick in the first slot and the apply those timings to all the sticks that are installed.

Generally, using "mixed memory" is a crap shoot. sometimes it works, sometimes it doesn't, and even if it does it "downclocks" one pair.

To completely avoid issues buy all the memory as one matched set.
 
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BonzaiDuck

Lifer
Jun 30, 2004
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Motherboards read the SPD table in the memory stick in the first slot and the apply those timings to all the sticks that are installed.

Generally, using "mixed memory" is a crap shoot. sometimes it works, sometimes it doesn't, and even if it does it "downclocks" one pair.

To completely avoid issues buy all the memory as one matched set.
No disagreement, but the two kits are from the same model-line, only differing in default stock-spec of speed and timings. It's likely that the faster set include the JEDEC and XMP options encoded in the slower set.

If they were of different manufacture and even different model lines (G.SKILL TridentZ versus Ripjaws, as example), I would still try and avoid it.

It may be a crap shoot, but it's probably worth trying. Note that the model-code for these "Fury" kits only differs in the speed spec and CAS latency. They're likely made from the same parts.
 
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Deight

Junior Member
Jun 29, 2018
3
1
16
Alright, thanks for all the help, I was going to try it out, but I realised I'd go for the long shot, future-proof options, sell my 2133 Mhz stick, and buy 2x Predator 3000 Mhz ones. Even tho my MB only supports 2133 Mhz ram (Asus B150-Pro), I will most likely change it in few months, remaining on the same socket, with a MB that has 3000 Mhz+ compatibility.
I really appreciate the help ! :)
 

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