I need to go out more....I understood every word

I appreciate those who count from 0 instead of 1.

Thank you so much - those kind of Videos really rock . You should do them more often, you are really doing great explaining that kind of stuff!

Good point that you can't test the IF with memory stresstests. In my case the 1900 IF passed Karhu without any problems, but playing BF V (yeah actually sometimes gaming^^) the whole system rebooted after some minutes. I had to raise voltages a little bit (Vsoc 1.15v and VDDG 1.1v) to have it completely stable. I think this video might be very helpful for some people, so thanks!

Dear Buildzoid. I have been researching which motherboard and cpu to be in my next 4 builds. (One for my dad, my best man, myself, and brother in law) and you have absolutely astounded me with your knowledge. It's surprising you don't have considerably more subscribers. When I watch other tech tubers, who I won't mention by name, they don't go anywhere near the detail you do. The first video of yours I watched was you going really in-depth on VRMs, I just watched all of your x570 videos and rather enjoyed your rants. Also, because of you, I have changed my mind on which motherboard I was going to get. I really think you should have more subscribers. I learned more watching your videos in the last few days than I have in the last 20 years of building systems. I'm just really impressed. I like how your videos don't have a lot of flash. It's substance. That matters far more to me than studio lighting and b roll of a system build. I wish you great success and look forward to more of your videos.

Good video. I knew CCD to CCD needed to go through IF but I didn't know CCX to another CCX on the same CCD also needed to go through IF. Makes the 3950x a bit more appealing since it has 4 cores per CCX vs 3 cores for the 3900x which could in theory be less reliant on IF if you're playing a game that uses only 4 cores, assuming Windows Scheduler is smart enough to run them on the same CCX.

if AMD will use interposers for Zen 3 they probably can get much higher FCLK (because silicon will clock higher than substrate connections)

Another awesome video as usual buildzoid! Im glad you're back!

G'day Buildzoid, I like the videos that focus on 1 topic, I've not been understanding the Core connections + Memory +Infinity Fabric & abbreviations but you picture & explanation just made it really simple, Thanks, I'm saving this in my favourites

You are the man! Thank you for share those valuable informations with us ;) I really wondered them.

Literally the only video I know that explained Ryzens memory system perfectly understandable . Highly appreciated and liked.

Thank you for this video! Really well done.

Really great video, explaining a lot! Thanks!

@Actually Hardcore Overclocking The Video was quite good but your diagram is not quite accurate. There is only a single interconnect that connects each of the CCds to the IO die and that Interconnect is chared by both CCX modules. There are two interconnects for the two die CPUs 3900x and 3950x. Each of the Memory related interconnects operate at a rate of FCLK x 32 Bytes/cycle. You can work out the max bandwidth by calculating it out. with 3600MT/s memory the total available bandwidth is 57.6GB/s. That is teh reason why the max throughput that you observed was 57GB/s even with higher clocked memory. Intel Ringbus runs the connectivity between CPU and memory at a badwidth determined by teh Cache multiplier. At x45 that is 144GB/s. Both the Infinity Fabric and Ringbus provide shared bandwidth for teh CPU accessing memory and the GPU accessing the L3 Cache to obtain instructions. Tested memory bandwidth on Intel remains constant and in excess of the maxumin throughput potential of teh DDR4 memory but with Ryzen, the tested throughput is only true when you are not running a game as the Interconnects Bandwidth at 1:1 matches the capacity of the Installed Ram. Running a GPU in a game over the shared bandwidth means that the CPU bandwidth to memory is compromised. As such, the CPU obtain data necessary to operate at full capacity. As you alluded to, a system with 2133 MT/s Ram with 1900FCLK will almost match a system with 2080TI running 3800MT/s Ram when a 3200 system will not in games.

Thank you! This helped me optimize my Ryzen 3900X! :)

This video was unusually good quality. Really interesting topic aswell! Keep up the good vids. :)

wow i never knew kermit knew so much about tech

Amazing video, thanks for the information.

Note that FCLK instability very often manifests itself differently than memory instability. When my FCLK was unstable I would get broken crackling audio and frequent long stutters in games without anything actually crashing. I tried pushing my SoC voltage up to 1.2 V and couldn't make 1900 MHz stable. I think it was actually getting worse at some point. I still seem to manage 1866 MHz at 1.12 V or so quite easily.

Thanks so Much ! Very well explain ! I will very like to see how the VRM perform in this new x570 motherboard ! Thanks

I bought an AHOC VRM shirt via Teespring and it is high quality and it even comes in rare tall sizes. Thanks for your content and information BZ!

This video is very good, i plan on overclocking my ram and this has helped me understand how all of this works

Didn't think I would understand any of this. but thanks to the avoidance of all the jargon combined with easy to understand abbreviations, I actually learnt quite a bit, Great job on the video.

very nice explained -as a follow up it would be interesting to see those settings directly in the bios... ( one time with cheap ram 3000 - 3200 mt and one time with 3800 mt ) :D

Thanks for the information. Good to know and it makes sense to me.

Did you do a video on that topic regarding zen and zen+ ? Awesome content as always AHC.

makes so much sense for how to optimizing parallel programs for ryzen, thanks

I bought the 4400 cl19 "(really good b-ie") Ram that you recommended in another video, and I have had some very good results from the sticks.

Your video's have learned met a lot over the last few weeks, I'm happy to have found your channel (y). You say in the beginning of this video that the memory controller is a mess but I haven't seen any proof of that in the video because it's just .... a little complicated haha :) Running a 3900X over here with G.Skill NEO (16-19-19-19-39-3600) 2 x 16 DRAM over here which works fine but doesn't seem to like overclocks so I'm quite happily running stock on CPU/DRAM/GPU(1080ti). Thank you for your great videos /me like !

Great video as usual Thank You!

Excellent explanation that is really helpful thanks

the memory math reminds me of the good ole athlon overclocking days, ah nostalgia.

Thanks buildzoid I had been discovering all this for my self the stability issues on full load and I came to the same conclusion cheers bud u smartie pants =)

Thanks for the amazing video. I now have graduated in how to run an amd CPU... Honestly you can tell how everyone was lost at the release. I wanted to buy a 3900x but when I saw what was going on on userbench, I'm just gonna wait for intel 10th gen and go from here. I'm not an intel fan, I'm glad to see amd come back to improve competition but man at least when you run a new intel cpu you know what you get right out of the box without marketing spiel.

Thanks a lot, that was helpful!

Could you please do a video about the performance of the 32gig samsung oem stick you showed us in a previous video and test how these oc on x570 platform in a 2 (64G) and 4 (128G) sticks setup?

I've never learned so much yet understand almost nothing before. Really good video, I'll definitely have to rewatch this multiple times to actually understand though lol

Wow! I was blind now i can see! Thank you for this perfect explanation.

I understand that MCLK is DDR4 over 2 and I understand the UCLK clocks the UMC and the UMC branches off to the CCD and then to a CCX, but none of this tells us why SM can't be in the MCU anymore? \o/ ;P

My dyslexia hates this video hahaha Thanks for all your very informative videos! They have helped me with my first pc build in a very long time, of which I will have all the parts tomorrow lol

Feels good to be back.

Very useful information.

Dropping my IF from 1800 to 1600 increased my core max boost by 100 mhz, which resulted in similar benchmark results when comparing 3600/1800 memory with 1800 IF to 3200/1600 memory with 1600 IF. Not sure if the instability at the higher speeds was caused by the CPU, memory, or the motherboard. Crazy amount of variables to peak performance these days.

Great work bud. 👍 Gonna be fun fine tuning mine when I get it. 😁 Wendel from Level1Tech has been on the case too and he's found some interesting info as well. 😉

o snap, i think u solved my issue, i was running my 3200 mhz kit at 3600 mhz (sorry mega ticks? kappa ) and 1900 fclk, so even though memtest came out 100% error free when i would encode long videos or game for a long time i would crash, so i was over stressing the infinity fabric and was also against your 166 rule, so i should keep it fclk = uclk so both at 1800, i am gonna try that right now, thanks bro

Brilliant explanation in laymans terms Buildzoid 👌

Oh, and Welcome Back! Gimp and I missed you.

Man, this guy is using GIMP, he could have used Adobe "Intel" optimized Photoshop but he is using GIMP

Thanks very much

Welcome back :)

Wow this video was super cool. Where did you learn all this? Also, what would you recommend for stress testing the entire system? P95 small FFTs?

Excellent video as aways. Iam surprised how dificult is to get correct information this days. That information about inter-ccx communication is really hard to find. please, tell us, where did you get it?

Great, i understand now why GCC was unstable but memtest was stable. Thx for this

Hope to see you redo this video for Ryzen 7000 and with DDR5 and such, even if it's essentially the same info

Hey Buildzoid, nice job! Can you make another similar video explaining ryzen 3000 memory system with diffrent memory configuration - single/dual rank, two sticks, four sticks, 2x8gb, 4x8gb etc? Some pros and cons, teoretical ideal setup.... Thank you :)

Welcome home, and i was wondering how slow ram needs to be before more fclk = better thanks. If you get a chance can you test your x470 gaming plus on a ryzen 3000 cpu, i can't pass memtest86+ 5.01 (fails in test 7) without either using single channel ram or disabling cores, i tested 2 ram kits w/ same results, not sure if it is the bios or a bad cpu, and if i turn off SMT and have all cores it locks up 1/2 way through test 7 in under 4 minutes; i have a 3600

Got my Trident Z RGB 3200MHz CL16 OC'd to 3600MHz CL16. So yeahh....

Thank You

About to pull the trigger on a 3600 and pair it with some gskill ripjaws 2x8gb sticks, 3400 cl 16 on the updated msi b450 tomahawk max. What memory profile do you recommend? I guess it will depend on how far my cpu and ram can go (and btw whats you opinion of this ram in particular, I read in foruns it can be sort of a gamble as you may get a good samsung die or really shitty micron one). Thank you bz, love your content 👍

75k subs.... damn thats alot!

HUB did a video on the ratios of UCLK and MCLK and 1:1 is definitely better. I recall performance gains from 10-20% from going from 3200 stock timings ram to up around 3700 with all the timing pulled tight. I recall OCing the UCLK more than the exact 1:1 resulted in a loss as well.

From this it looks reasonable for Zen4 to have 8 cores per CCX and 2 CCX per CCD. Got to keep the latencies in check when scaling up the core count.

Question: my initial thought was that the FCLK worked best when equal to MCLK ie. 3600 kit to give 1800Mt/s and clock the infinity fabric (fclk) to 1800. You suggest this is not optimal and performance can be improved by having an offset of 166 between the two. So if you have an fclk of 1800 you need a uclk

Since DDR stands for Double Data Rate, it is correct to call it 4000MHz when the MCLK is really 2000MHz. Because that is double the data rate. /s

Hey i have a 980ti and 970 that may still work but as of now do not any chance you would want them for free?

The prodigal son returns! About damn time 😁 This is going to help me when I get my Ryzen 5 3600 and 16GB (2x8) of 3200 MHz Micron E-Die

thank you

i'm Commander Shepard and this is my favorite Ryzen video on the Citadel. (well maybe, idunno but either way yes, this video is useful, and yes, it is interesting. no need to worry about that)

Hi I would like to make a question: I have bought these RAM sticks "G.Skill TridentZ Neo 16GB DDR4-3600MHz (F4-3600C16D-16GTZNC)" because they were way cheap and I didn't know they were Hynix RAM sticks. I do NOT intend to OC them, I only OC the CPU. What you suggest I do? Keep them or buy "G.Skill TridentZ Neo 16GB DDR4-3600MHz (F4-3600C16D-16GTZN)" RAM? I really trust your opinion and would really love your advise. I have an Asus Rog Crosshair VII Hero MoBo combined with a 3600 Ryzen 5 CPU. Best

can you do a video about epyc too? my company plans to buy new servers at the end of the year if dell delivers... so I would be really interested in that. :)

In my case 1900 FCLK stable (Ryzen5 3600) pass test AIDA64, linx, "AAA Game" about 1 hour all goes well. (RAM 3200cl14 SOC voltage 0.975)

Since the IO die can be binned as well, I wonder if we'll see over 1900MHz FCLK stable on the 3950x. From what I've seen only the 3600 has a problem getting 1800MHz, so they probably get all the dud IO dies.

Hi, Have you made a video about tuning memory for the Ryzen 3000?

There might be an octa-channel TR variant in the works, but that will require new motherboards.

At what RAM clock rate would it be more beneficial to downclock and max out FCLK? Is 2666 RAM with 1900 FCLK better than 3200 with 1:1?

yea, i stopped running 1900 fclk myself because it was too borderline stable.

This is very helpful. I can't wait to break my future ryzen 3k!

I still often wonder how the latency and overall performance would be with 4000 MT RAM, 2000 mhz uclk 2000 mhz fclk and 4000 mhz fixed core clock. Would probably take LN2 to reach those uclk and fclk if it's even possible, but it'd be neat to see what a 2:1 core to everything else would do.

Hi I have 3800mhz CL18 ram and I cant touch the sub timings. Especially the TFC wont go below 560 at 3800mhz CL18. Is this normal? How to lower TFC

I recently discovered the hard way that more SoC voltage is not the way to get on zen2. I was playing around with a friends 3600, pushed IF to 1900 at 1.11v (1.1v GET), and was getting WHEA errors. Tried pushing more SoC and things just got worse and worse, at 1.16v (1.15v GET) things like video playback would chug and audio would crackle, and there were far more WHEA errors. I was so confused, dropped SoC to 1.09v and all the issues disappeared and things were stable. I had never seen this issue before and I've messed around with 9 or 10 different ryzen systems, only 4 or 5 were zen2, and never saw issues up to 1.2v SoC on zen/+.

Wow I learned a lot.

I had a question but it got answered at the end.

Would running MCLK/FCLK at some other, simple-ish fraction help in non 1/1 cases over picking some random number, say 5/4 or 6/5 (in your example 1760 or 1833MHz)?

Welcome back

Please, man, can you make some notes and video about T-Topology and Daisy Chain. I learned so much this time, and eager to know something, really something about RAM topology and how it works in connection with CPU. I could not find anything in English about it. Grateful. Thanks.

what if i bclk oc and its a really strange number like 3607mhz on memory? should it be the same for the bloody mhz or ia it a bit forgiving?

@Actually Hardcore Overclocking - was it just a simplification, or does the memory layout really mix a daisy chain and t-shape layout for each channel? If so, wouldn't it have some negative impact on stability and performance?

if my FCLK is set to 1900 I have a 1 in 5 chance of not posting on a cold boot. Im still chasing the 3800 dream. It does post after bios changes and passes stress tests but the bios resets are annoying in that 1 in 5 chance. Im wondering if its the CAD BUS Strength Ive eliminated that its not the voltages or soc Voltage cause I gone up to stupid amounts and even then I get the same issue. at 3733mhz I have it 100% stable but im still gunning for 3800 :( at the moment I took a break and just worked on super tight timings for 3733mhz I have cl 13 at the moment probably will need to change back to cl 14. It currently at 1.52volt though for me to maintain stable cl 13. 1.2soc Volt vddg 1.5 vddp 1.1 (might be the other way around i forget which off the top of my head on vddg/vddp)

I know I'm just behind the times, but does any of this apply to Zen+ (2700X)? Is there already a similar, older, video specifically about that?

14:05 - lol I can relate because I have some Micron D9TGG that doesnt OC for shit and some Hynix BJR that only gets to 3066Mhz and no more where as my hynix AFR tops out at 3800mhz, fun fact: these 4 dimms with 3 different ICs (2 being AFR) is the same 4X4GB Kit of kingston HyperX 2400Mhz (DDR4)

Is there a video like this for Ryzen 1000 and 2000 series? How does it differ with the current 3000 series?

Could have drawn a Crossbar (Xbar) in the IO - die :)

Is it worth it doing the FCLK OC if the kit is working 3200 (1600mhz) and the CPU can go 1800-1833 with the FCLK? As the gap narrows to the top speeds?

Question: people seem to think that you always need to run 1:1 on Ryzen 3000, but from what i've seen it is beneficial to overclock IF (FCLK i believe) even if it will no longer run 1:1 with RAM. The only way non-1:1 becomes a problem is if you are running RAM past 3800Mhz in 2:1 mode. So for example pushing FCLK to 1900 but MCLK is at 1600 (3200Mhz RAM). By this logic people seem to think that you should also run FCLK at 1600 so it would be 1:1 Hope someone can clear this up for me.

So the CLUCK has to run twice as fast as the FUCKLER...got it! Thanks. 😏

Hey Buildzoid, did you see two wild and crazy guys in Czechoslovakia?

Hey Buildzoid, guys here!

about the memory channels -are itx and dtx boards that only offer 2 memory slots offering them each on a separate channel? do you get the same benefit if you only use 1 card in a channel?

So, on the Ryzen 7/9 DDR 3600 is ideal. MCLK, UCLK, and FCLK is 1800MHz. I have DDR 3200 with Samsung DIE's, so hopefully I can get it from 1600 to 1800.

does FCLK scale with LN2?