RAM rank question

I just ordered a Framework laptop with an i7-1185G7 processor :partying_face:

I’m wondering if it will make any difference if I have two single-ranked RAM sticks or two dual-ranked RAM sticks.

For example, any difference if I go with two crucial ct16g4sfra32a compared to two ct16g4sfd832a sticks? (The only difference is that one is Dual Ranked • x8 based and the other not)

If not, would a difference be seen with only one stick of RAM (same memory but one dual and the other single-ranked)?

  • Would this mean that when two sticks of RAM are used only one rank is used?

  • Would this mean that having 2 - 8gb single ranked memory stick is equivalent to having 1 - 16gb dual ranked memory sticks?

(Both referenced kits are marked as compatible in the knowledge base.)

On my end, I would suppose that there would be a difference but I would like to have a confirmation.

Context:

Some reports indicated a significant impact on performances on some specific devices and tests (On some gaming laptops a difference between 10 and 20% has been seen).

This might not be the case for most usages of the Framework laptop but I plan to use in-memory databases and it could make a significant difference for me.

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Yes, dual ranked is better than single rank, there are various benchmarks by GamersNexus and HardwareUnboxed or Actually Hardcore Overclocking to demonstrate this

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Let me add on tho-a single rank dual channel kit will still outperform a dual rank single stick

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Yes it’s always better to use two sticks, because the cpu has a dual-channel memory controller, so each dimm slot is a dedicated memory channel and by populating both of them you will get the full bandwidth offered by the platform. Even if one single rank dimm is 10-20% slower than one x8 dual rank dimm, having two of them is still double the bandwidth and is worth slower individual sticks.

The optimal memory configuration is two sticks of x8-based dual rank dimms (ct16g4sfd832a in your case)

Hope that makes sense.

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Hi,

I have the crucial ct16g4sfra32a memory installed in mine (2x 16GB); I ordered them with my laptop so I did not go down the rabid hole of memory selection until after I already committed. Smart, I know.

Here is what I learned so far about this particular set of memory:
It is annoyingly hard to find in-depth data sheets from crucial, but you can find ones for micron. After all, Crucial is a part of Micron so they use Micron chips anyway. The chips can be identified by the 5 letter/digit code, from that you can get to the data sheets of the chips (NOT the module)

In my case it is indeed x8 width memory, with 1Gb per chip (eight of them per side, both sides on each module = 16Gb). Code is D8BPJ on my modules.

CPU-Z shows the Rank as dual, as well as channel as dual (which makes sense with 2x16 config). Not sure if this helps, but I thought it might be worth it to give a few more data points to the discussion.

If anyone has better resources or knows how to more definitively read the products codes (so you don’t have to buy and test them), I would be glad to learn more.

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Thanks for the answers and for clearing my confusion around the channels and the ranks :pray:

Based on the answers it seems the best possible option is to go with two dual-rank memory sticks.

If this might be useful to someone on my end I choose to go with two Kingston Fury KF432S20IB1K2 16GB CL20 memory sticks.

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They may not work properly, CL20 sounds like an XMP profile and that is unsupported

They may default to 2666MT/s, instead of the 3200MT/s that you want

https://www.crucial.com/memory/ddr4/ct2k16g4sfd832a

I would buy the above or the 64GB version if you want to max out the RAM

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They’re actually 1.2V kits, however, from what I’ve seen ONLY the 3200 CL20 kits have booted, I don’t know if anyone has run a stability test with them. I tried the 2933 CL17 version I had lying around and another poster tried the 2666 version, neither would boot.
The problem with these kits is their JEDEC timings are all fairly aggressive, they don’t have standard JEDEC frequencies and timings. Their JEDEC profiles are identical to their XMP profiles (at least in terms of primary and secondary timings).

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Is that not what XMP is? JEDEC standard is CL22 I believe

Glancing at the spec sheet it does use XMP profiles-I really don’t think it will work right although I would be happy to be wrong, lower timings is always better at the same speed

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Might be semantics but I guess what I mean to say is the non-XMP profiles have the same frequency and timings as the XMP profiles. They’re marketed as running without XMP but most of the kits currently have problems running on the Framework.

That said, I’m not sure it’s even guaranteed the 32GB kit is dual rank. edit nevermind I double checked the spec sheet. Manufacturers have increasingly been shipping single rank 16GB sticks. Generally I assume I’ll get single rank unless it’s specifically marked as dual rank, and I think dual rank 3200 CL22 probably matches or outperforms 3200 CL20 single rank.

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It better be, it’s marketed as dual rank along with their 64GB kit

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Oh you’re right, sorry I just double checked the spec sheet.

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@reverse_thrust I sounded way more ominous than I meant to be-almost threatening lol

I hope Framework will enable XMP support in a BIOS update to get these laptops to the best performance possible

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Yes, the KF432S20IB1K2 are working flawlessly for me :tada: Checked the timings, it’s the right profile that’s used with my laptop.

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Given the title of this thread I thought it might also be interesting to point out that there are 2 variants of these 16G Fury CL20 SODIMMS: KF432S20IB_16 (single rank) and KF432S20IB1_16 (dual rank). Both are also available in the very similarly named kits (KF432S20IBK2_32 vs KF432S20IB1K2_32)

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I have bought the Fury CL20 1.2V ram and have the single rank version. I did look for the dual rank but its out of stock everywhere I look or just crazy price in the UK. So I’m fine with the single rank. Most other 3200 DDR4 stuff is 1.35v which I avoided. Will probably still be better than the bog standard single stick stuff the usual makers use.

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I bought 2 individual dual rank SODIMMS from Amazon UK: https://smile.amazon.co.uk/dp/B097TNRLJ9 … maybe that’s still an option?

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All I can say for sure is that I’ve had way too much time preparing for this laptop to arrive since UK pre-orders opened up. Completely failed to get a P31 Gold SSD (order was lost after shipping from Amazon US & I didn’t want to risk another order), but either variant of the Kingston CL20 RAM seem to be thing to have…

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Yeah I think at this point it will be half a dozen of one and half a dozen of the other.

We can check benchmarks in a couple of weeks! :smiley:

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Edit:
Saw most of my questions and remarks were allready discussed further up. I guess I was to tired to notice :slight_smile:

Do they work for you?
I also bought a kingston fury impact ram kit with an XMP Profile, although a slightly different one (KF426S15IB1K2/32 - 2666Mhz with CL15 - 17 -17) and I can’t get my framework to accept them both. Only the channel 1 can read the ram, if I try channel 0 I get a ram failure message.
The support told me it is due to the xmp profile but appearantly the ones you linked have that too, so I’m a little curious (and I have to get a new kit appearantly which sucks a bit, they are not that cheap).

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