Reason why SO-DIMM to DIMM adapters don't work with Ryzen?

Hardware Motherboards
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Hi,

for experimentation I got a pair of adapters that let you install SO-DIMM sticks in full-size DIMM slots.

Just like in this video, Intel systems (Skylake-C236 (ASUS P10S WS) and Haswell-EP-X99 (ASRock X99 WS)) work fine with these adapters (by the look of the pcb my adapters seem to be exactly the same models).

But a Ryzen system (ASRock X470 Taichi/UEFI 3.20/2600X) doesn’t post (0d) (also, just like in the referenced video).

I could even test a standard OEM SK Hynix module that worked fine in a Zen+ laptop (Ryzen 5 3550H) - no luck there.

Is there a “simple” reason why this cannot work with Ryzen motherboards?

In the near future I wanted to check if I could speed up a locked down Coffee Lake-i7 OEM system with no dedicated GPU by swapping the standard DDR4-2666 with -3200 ones, since the iGPU should like the additional bandwith.

Since there is no BIOS access I wanted to use Thaiphoon Burner to alter the G.Skill-3200-Samsung B-die-SO-DIMMs’ SPD so that the higher frequency is “force fed” to the CPU’s IMC after a CMOS reset.

I know that this is possible since I accidentally overclocked an Ivy Bridge laptop by installing Kingston HyperX-DDR3-2133 modules that use that mechanism to “auto-overclock” systems.

Unfortunately Intel seems to have locked software access to the SPD on a firmware level on all DDR4 platforms, so using an existing Ryzen system for the job with these SO-DIMM adapters would have been swell, as a Normie-Pleb I don’t feel competent enough to modify of my Intel C236/X99 systems.

Unfortunately I do no longer have access to that mentioned Zen+ laptop and I don’t have any family or friends that have an AMD-DDR4 laptop.

Since this is also my first post I’d like to say hello - been a news episode watcher for a little while and since I got some nice inspiration from a video recommending used enterprise hardware even as a Normie I signed up here to hopefully find answers to various questions and on patreon to show a little support and gratitude for presenting rather niche content in a way plebs can follow :wink:

Regards,
aBavarian Normie Pleb

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Zen and Zen+ (ryzen 1000 and 2000) are a bit fineky with RAM to begin with. Depending on the quality of the the adapter and the RAM itself, this may just att up to more than the IMC can handle.

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you might be able to use these adapters if you pre-set the timings to 1866 or 2133.

The imc on ryzen is basically hard wired into the memory where as on intel it’ll work almost async. So intel is very forgiving with things like trace length. ryzen is not. It’s because ryzen depends a lot more on memory speed/stability since it’s linked to infinity fabric speed.

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I was going to ask why sodimms

And then I saw bavaria

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Infinity fabric as a reason sounds reasonable.

I also tried that (1866), since I just found out around the same time that my X99 boards don’t like (L)RDIMMs that are speced for more than 2400 MHz in memory slot A1 (change from “Auto” to 2133 or 2400 and they are fine, depending on the CPU, whether it’s Haswell- or Broadwell-EP)

Also tried every slot individually on the Ryzen system.

Can you evaluate if it’s “easily” possible to mod a C236 motherboard BIOS (ASUS P10S WS with “USB Flashback” feature) to be able to modify SO-DIMMs that aren’t write-protected and are seated on adapters?

http://www.softnology.biz/tips_spdwritecap.html

@FaunCB

Yeah, I’m so plebby that my laptop still uses DDR3-SO-DIMM :wink:

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I have asked the same question in regards to a 6770HQ with an Iris 580 iGPU and the answer for that was no, no benefit form faster ram. The topic is around here and I will link to it later if you want but right now I am on a short lunch break.

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Thanks for your feedback!

I’m curious myself to try it out; since I’m increasing the memory capacity in any case and I’ve already ordered the mentioned G.Skill-3200-SO-DIMMs with Samsung B-die DRAM, it wouldn’t be “much” extra work to change their SPD - if one of the systems I personally have access to can be modified to write SPD details via Thaiphoon Burner et al.

If possible I always use systems with ECC memory but if that’s not an option I choose “the best” non-ECC memory around to reduce the likelihood of memory errors even without overclocking.

I just noticed that the normal desktop GUI with a 10-bit-60 Hz-UHD display (Dell UP2718Q) is a bit laggy with the Intel UHD 620 graphics, every little bit more “oomph” is welcome since a Thunderbolt eGPU addition is not an option (at this point in time).

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I am honestly amazed you are running 2160p on an Intel iGPU. They are notorious for dropping out and having lots of issues running one.

Mine will display but it will flash black every few minutes at that resolution. So I just run 1080p on 2160p screens.

Edit, here was my findings, it was related to game where there is no benefit from fast RAM, but maybe the desktop will feel better

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We haven’t met. I’m master pleb. We’ll talk in lounge later.

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Nice coincidink: Found out today that the ASUS P10S WS has a regular “Enable SPD write” option (the very last one in the manual timings listing) :slight_smile:

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Say are you suggesting (because I don’t know) that the memory controller on ryzen is a synchronous memory controller I.e it has a set of speeds and timings it can run at and the memory must match it?

Where as Intel has an asynchronous design?

That’s an interesting proposition I never looked deeper into ryzen