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AMD Zen 2 Memory Performance Scaling with Ryzen 9 3900X

What the point in running 3600 with those horrendous primary timings? Ryzen first gen and Ryzen+ have no problem hitting 3533 with 14-14-14-24-38 and some of the nicer silicon on Ryzen+ can do 3600 with the same primaries. This is all with secondary and tertiary timings tightened nicely. Theres literally no point in running 3600 @ cl17 when 3466 @ cl14 is going to walk all over it. For that matter, 4000 @ cl20 is just awful and again in most scenarios 3466 - 3600 @ cl14 is going to destroy it. Only reason to ever use those higher freqs will be for applications that only care about raw bandwidth and not latency. My 3700x will arrive Wednesday then ill see how real memory scaling on Ryzen 2nd gen performs. I look forward to seeing how far we can push it over on the ROG C7H and DRAM Calc threads @ Overclock.net ;)
The idea was to use memory timings that the masses can actually afford, not some halo numbers. I'll look at getting some runs in with tighter timings later this week when things are bit less crazy
 
The idea was to use memory timings that the masses can actually afford, not some halo numbers. I'll look at getting some runs in with tighter timings later this week when things are bit less crazy

By looking at the title of the review, it would suggest the point was to how memory performance scales on Ryzen 2nd gen. Also, that 3200 14-14-14-34-1T setup is Samsung B-die which is still fairly expensive. If there were to be a fair scaling comparison highlighting any gains in performance from this gen then Id say keep it B Die across the kits. say like the f4-3200c14 kit, the f4-3600c15 kit (at Cl14 of course, instead of 15) and then f4-4000c17. Just to make it the most simplistic, grab the 4000 cl17 kit and run it at 3200 cl14, 3600 cl14, and 4000 cl17 but then take it further by overclocking the Fclk as high as you can get it (since the memory controller is going to drop to 2:1) while maintaining stability of course. That would at least show if its worth even exceeding 3600 and overclocking the fclk to try and mitigate the performance loss from the memory controller drop above 3600.
 
and overclocking the fclk to try and mitigate the performance loss from the memory controller drop above 3600.
Why not overclock fclk all the time?
 
It might become unstable over 1800MHz?

This is something we need to investigate and see what happens with e.g. SoC voltages (are there new ones for the I/O die or?) and how new UEFI/AGESA code maybe affects it too.

Lots to play with! :)
 
It might become unstable over 1800MHz?
My 3900X can handle 1800 MHz Infinity Fabric, 100% stable. Next setting, 1866 I think, crashes within 30 seconds of load applied
 
Exactly, so there's a good reason not to OC it. ;) 3600 is presumably not really a "full" OC (even if stock is 3200) if they are including 3600 sticks in the review kits.

It will be interesting to compare mine and @CjMitsuki's to see if there is an element of Si lottery involved.

Are you able to change the IF voltage or is it tied to the main SoC or just not enabled in the UEFI (yet)?
 
Thanks for the review.I do not expect you to do every setting on memory for everyones set of DDR4 Kits.Especially at this time with video card releases/CPU releases ,must just be crazy.You covered the normal kits out there.
I waiting on my Ryzen 3xxx to arrive and I have a DDR4 4000 kit I will be testing but I already know the answer.
I think I will test but beyond 3600Mhz I am not sure what settings I can use yet to be stable on my cheap X470 MSI Gaming Plus Motherboard.
♦ 2133Mhz (16GB)CL10-10-10-10-21
♦ 2400mhz (16GB)CL10-11-11-11-21
♦ 3200mhz (16GB)CL14-14-14-14-28
♦ 3600mhz (16GB)CL14-15-15-15-42


Again the review is helpful and appreciated for us regular user's.
 
It might be, but you may be better to wait a bit and see what results people get.

I have some nice Team 3733MHz I will be playing with on a 3900X later in the week.

You can also maybe get some 3200 CL14 and find they will go higher with looser timings and allow you to find a good sweet spot and might cost less, going for 3200 versus slower should guarantee you will get at least the official spec of 3200MHz and not be hampering the CPU, more overall performance is then a bonus.
 
An interesting test.
I was looking for this information. Thank you very much.

I still wonder what will be like no 2x8 but 4x8GB?
What will the performance and clock memory of 3600 look like for 4 dice?
 
Pity that there is no test of Factorio, one of the few games that really depend on memory bandwidth and latency. Old Ryzens did not do well at all.

@W1zzard would you be interested in benching Factorio? Gettings some huge saves would not be a problem.

Some sources for reference:
reddit.com/r/factorio/comments/bdr5kz/psa_factorio_have_benchmark_option_to_measure_ups/
reddit.com/r/factorio/comments/4h647g/factorio_performance_test_cpuram_based_fpsups/
https://forums.factorio.com/viewtopic.php?p=441170#p441170
 
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@Marucins I will be using 4 x 8GB Team modules.
 
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This is a helpful review. I'm running 64GB of 2400mhz RAM I bought years ago when higher speeds weren't as common, especially at high capacities.

Helps to know it won't starve a 12c/24t CPU.

Thank you for including 2400mhz in your review.
 
The idea was to use memory timings that the masses can actually afford, not some halo numbers. I'll look at getting some runs in with tighter timings later this week when things are bit less crazy
Really looking forward to this, thank you so much for your tests!
 
I have met such information and I want to verify it.

Ryzen 3000 processors support RAM memory clocked up to DDR-3200. This corresponds to the fastest timing adopted so far by the JEDEC consortium, which includes all major memory and processor manufacturers, including AMD and Intel. AMD guarantees that the processor can work with such a speed memory:
  • DDR-3200 - if 2 memory modules are installed,
  • DDR-2933 - if 4 single-sided memory modules have been installed,
  • DDR-2666 - if 4 double-sided memory modules are installed.
I want to buy 4x 3600 and if it slows me down to 3200 it will be fine, but below... :\
 
@Marucins If you don't see a post from me over the next few days, PM me to remind me and as mentioned, I will update with how I get on with the 3733 kit. It easily does 3200 (and 3333CL16) with a 2700X so I would think 4 sticks SR should be easy with Zen 2.

They are Samsung B-die, SR.

I also imagine Zen 2+/Zen 3 will improve things further, so getting a bit faster now, may work out well if you plan to pop in a new CPU next year.

What board do you have? Apparently the TaiChi X570 has a T topology which should be better for 4 modules.
 
OK!

It's getting ready to change and update the rig. I like X570 AORUS XTREME and I will probably buy this mob.

If the PC upgrade, then there is a change in memory - now I don't know if I should buy 2 dice or 4. I don't want the frequency to slow down because I will fill 4 memory banks.
 
One thing to watch, while I too like the idea of the AE (passive CS cooling), it apparently only has a 128Mb flash chip, so could run into issues with next year's CPU like some boards are seeing with Zen2.

It's mind boggling that they would cheap out on the flash size on such a board. :confused::eek::kookoo:

Go for 2 x 16GB sticks if you can find the right speed at the right price. Then you have less issues with 4 sticks and the option to easily go to 64GB later.

3900X in the house ...


Holy BLEEEP, I wasn't expecting this kind of difference in cache speed!

This is with the same BIOS and RAM settings (actually I think they were tuned a little faster on the 2700X) ....


126714



I just set 16-16-16-38 and 48 for tRC I think it was and the rest on Auto and it's pretty good other than a little loss of read and write but I'm sure tweaking up the sub timings will easily sort that out.


126715


XMP @ 2733MHz didn't boot but I didn't try training it up yet either. ;)

Update: Lots of GSOD, I'm not too happy with the ASRock BIOS, it needs the 1.0.0.3 update IMO ASAP.
 
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People seem to forget memory overclocking is a thing that can be done, so buy ludicrously expensive memory kits. 4000+ MHz kits are just stupid and usually have awful timings anyway. Literally, just get a cheap B-die kit and either overclock it yourself or use the DRAM Calculator for Ryzen...
I got 32gb 3866 MHz CL18 cause I found a decent deal when ram prices were stupidly high and run it at 3200 MHz CL14-14-14-28 @ 1.4V (cause Zen+ sucks for memory overclocking)
 
People seem to forget memory overclocking is a thing that can be done, so buy ludicrously expensive memory kits. 4000+ MHz kits are just stupid and usually have awful timings anyway. Literally, just get a cheap B-die kit and either overclock it yourself or use the DRAM Calculator for Ryzen...
I got 32gb 3866 MHz CL18 cause I found a decent deal when ram prices were stupidly high and run it at 3200 MHz CL14-14-14-28 @ 1.4V (cause Zen+ sucks for memory overclocking)

I agreed with you about 4 ghz+ memory kits. Way to exspensive and for ryzen 3000 memory above 3733 mhz split the infinity fabrik in two so the devider is 2:1 while below the fabrik runs 1:1 so over 3733 mhz you lose transfer speed on the infinity fabrik redusing data transfer between cpu and memory and may in some cases cause performance lose even throw the memory is running 4 ghz+.

I will say depending on once memory buget stick to between 3200 mhz and 3600 mhz memory. You are better of with lower memory clock and low timings than high clock and timings. Specially above 3733 mhz. The only good reason i can think of to why buy 4 ghz or more momory clock, would be to run them at exsample 3600 mhz but to push timings even lower.
 
I agreed with you about 4 ghz+ memory kits. Way to exspensive and for ryzen 3000 memory above 3733 mhz split the infinity fabrik in two so the devider is 2:1 while below the fabrik runs 1:1 so over 3733 mhz you lose transfer speed on the infinity fabrik redusing data transfer between cpu and memory and may in some cases cause performance lose even throw the memory is running 4 ghz+.

I will say depending on once memory buget stick to between 3200 mhz and 3600 mhz memory. You are better of with lower memory clock and low timings than high clock and timings. Specially above 3733 mhz. The only good reason i can think of to why buy 4 ghz or more momory clock, would be to run them at exsample 3600 mhz but to push timings even lower.
RAM is not exclusive to the Zen platform, 4000mhz kits are often used on X299 for numerous reasons for example and there is large gains to be had all the way through from 2400-4000 on skylake-X.
As for ryzen, above 3733 will not always set the IF links to 2:1, AMD Robert already confirmed above 3733 can run on the IF links 1:1 on good cpus that win the silicon lottery or have a good memory controller and such.
The best investment for zen is bdie kits on sale so usually 14-14-14 or 16-16-16 or similar at around 3600 for the best performance.
 
RAM is not exclusive to the Zen platform, 4000mhz kits are often used on X299 for numerous reasons for example and there is large gains to be had all the way through from 2400-4000 on skylake-X.
As for ryzen, above 3733 will not always set the IF links to 2:1, AMD Robert already confirmed above 3733 can run on the IF links 1:1 on good cpus that win the silicon lottery or have a good memory controller and such.
The best investment for zen is bdie kits on sale so usually 14-14-14 or 16-16-16 or similar at around 3600 for the best performance.

Yeah its different with intel, but right now we talk ryzen and memory. But i have not seen that he has said that good cpu's can run faster memory with out change fabrik clock to 2:1. Maybe it would be a good idea waiting buying memory as i am planning to get a ryzen 9 3950X and it shut get binned chiplets, maybe that also is the case with the i/o chip as well so it can run higher memory with out going in to 2:1 mode.
 
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