For a CPU that "loves fast RAM" the Threadripper sure hates compatibility...

Raizor

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Apr 26, 2018
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I bought 3200 Gskill RAM - off the compatibility list from my X399 Taichi motherboard - and I couldn't get it above 2933 Mhz.

So - at the suggestion of YouTubers and Forum comments - I purchased 64 GB of Gskill 3400 that WAS on the compatibility list.

NOW - I cant even get over 2134.

Is this a common problem? I have no idea where to begin on this. I've overclocked my CPU to 4.1 - increased my RAM voltage to 1.380 - nothing works.

I truly don't understand how or why some people just magically get their CPUs to run high speed ram and some people get screwed.

AMD TR and RAM sticks should totally come with a warning for this kind of thing imo.
 

coercitiv

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So - at the suggestion of YouTubers and Forum comments - I purchased 64 GB of Gskill 3400 that WAS on the compatibility list.
Check the compatibility list again, as far as I can tell it only lists 3466Mhz RAM in 32GB configurations max. (8GB DIMMs in 4 slots)
 
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Raizor

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F4-3400C16Q-64GTZ

This is what I'm using.

It says "3200" - but according to GSkills website - its actually 3400.

It's on the compatibility list.
 

Raizor

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Apr 26, 2018
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Still doesnt explain why suddenly I can't get to 2933 with RAM thats actually ON the compatibility list as opposed to the RAM that wasn't even on the list.
 

coercitiv

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F4-3400C16Q-64GTZ
They listed 3200 rating for your memory in a 2 x DIMM config.

DHuN0PI.png
 

Markfw

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Still doesnt explain why suddenly I can't get to 2933 with RAM thats actually ON the compatibility list as opposed to the RAM that wasn't even on the list.
Compatibility does not mean it will run at rated speed. Is it samsung b-die ? It looks like it. What motherboard ? Did you try 3200 speed ? Or 2933 ?
I am pretty sure my friend got 64 gig with memory close to that, to run@2933 on a Taichi. The motherboard DOES make a difference.

I reread-, yea you have the X399 Taichi. Maybe a bios update ?
 
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PliotronX

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This has been an issue since DDR1, more banks of memory places a higher strain on the memory controller even when it was in the northbridge. I was in a constant debate over running less ram with command rate 1T because 2T hit performance more than any other timing. Not to say the Zen memory controller is bad, just not as mature as Intels and Zen has the special condition of IF being synced with the ram frequency.
 
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IEC

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You generally won't be able to run single-rank timings on dual-rank modules (unless you won the silicon lottery). If you are using default timings it's likely too aggressive for the memory due to you having a 4x DR configuration.

At minimum, you will have to loosen timings and/or possibly settle for less speed. And/or crank up the voltage a bit (1.4V) to get higher clocks. If your memory modules are Samsung B-die I wouldn't be surprised if you can get 2933/3066.

I can get 3200 CL14 with 2 DPC using 4x 8GB single-rank Samsung B-die on AM4, and previously had no issue getting 3466 clocks on Threadripper using 4x 8GB single-rank Samsung B-die.

If you want high clocks + low latency, you are limited to 4x 8GB modules on TR4 unless you want to tinker with subtimings.
 
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tamz_msc

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Whenever you hear about people talking about fast memory and tight timings, it is single-rank memory that is being considered. That means 2x8GB for Ryzen and 4x8GB for Threadripper. The best Samsung B-die bin in a dual-rank config, which is usually 16GB DIMMs, is 3200 MHz CL-14-14-14-34.

It is usually rare for Ryzen to work with dual-rank 2x16 GB memory at a speed/latency combination better than that. With quad-channel on TR, you should be able to get to 2933 on 4x16GB dual rank like Markfw said.
 
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Raizor

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Apr 26, 2018
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Oh well - I guess 64 GB is overkill anyway. Maybe a Bios update, or CPU driver update will come out that will change all this.
 

Raizor

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I put the 64 GB back in and tried one more thing - I tried dropping it down to its lowest profile - below 2134 - and it won't work at anything but 2134. How does that make sense?
 

Kenmitch

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That does sound weird. Maybe you tinkered around so much the motherboard is in brain fart mode?

Maybe remove all sticks and reset the cmos. It won't boot up but maybe if you power it on without the sticks it'll snap out of it. Won't take but a couple of minutes to try and see.
 

IEC

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Can you take a picture of the slots you have your memory in? They have to be patterned in a certain way if you are using 4 sticks.
 

PingSpike

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On a regular Ryzen AM4 system if I wanted to run 24-32GB of ram...preferably fast, what kind of ram should I look for? And what can I reasonably expect?
 

IEC

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On a regular Ryzen AM4 system if I wanted to run 24-32GB of ram...preferably fast, what kind of ram should I look for? And what can I reasonably expect?

4 sticks of memory using Samsung B-die ICs = 3200 CL14 in 8GB single-rank DIMMs. Preferably as a quad-channel G.Skill kit or similar. 3600 CL15 is the better bin (but even more expensive). May need to bump voltage up from 1.35V to 1.38V or so, and/or relax a few subtimings depending on the motherboard. A high-end X370 or X470 board along with a Ryzen 2000-series chip increases your chances of success.

I used a Gigabyte X370 Gaming K7 board with a 3200 CL14 quad channel kit of G.Skill memory to achieve 3200 with 4 DIMMs shortly after Ryzen's launch:
https://postimg.cc/image/5n0puicd5/

Several AGESA and UEFI updates later, that is still the configuration used in that board but a lot of those metrics (bandwidth, latency, etc.) have improved. I'm planning on testing that board/memory config with my 2700X this weekend so I'll try to tag you in an update when I have a chance.
 

whm1974

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Oh well - I guess 64 GB is overkill anyway. Maybe a Bios update, or CPU driver update will come out that will change all this.
For a Threadripper build? I doubt very much that 64GB will be overkill for that type of HEDT CPU. Especially if you have 12c/24t or more.
 

eek2121

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The RAM is dual rank, you should have paid more attention to the compatibility list.
 

eek2121

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4 sticks of memory using Samsung B-die ICs = 3200 CL14 in 8GB single-rank DIMMs. Preferably as a quad-channel G.Skill kit or similar. 3600 CL15 is the better bin (but even more expensive). May need to bump voltage up from 1.35V to 1.38V or so, and/or relax a few subtimings depending on the motherboard. A high-end X370 or X470 board along with a Ryzen 2000-series chip increases your chances of success.

I used a Gigabyte X370 Gaming K7 board with a 3200 CL14 quad channel kit of G.Skill memory to achieve 3200 with 4 DIMMs shortly after Ryzen's launch:
https://postimg.cc/image/5n0puicd5/

Several AGESA and UEFI updates later, that is still the configuration used in that board but a lot of those metrics (bandwidth, latency, etc.) have improved. I'm planning on testing that board/memory config with my 2700X this weekend so I'll try to tag you in an update when I have a chance.

We need a new method for dealing with RAM. Honestly, WAAY back in the day I had no issues using RAM in an Intel, AMD, or Cyrix machine. It's gotten to the point now where XFR will work or it won't, and sometimes the system won't even boot at JEDEC rated speeds. IMO JEDEC should require certification for XFR DIMMs and manufacturers should do a better job overall.