Ryzen 3900X can't clock 1800MHz Infinity Fabric with 3600 CL14. Disappointed with Ryzen.

[Cowboystrekk]

TRFC has a large impact on latency and also gamingoerformance. Micron is worst at that timing. Samsung can often run below 300, Hynix below 400, but Micron often troubles with less than 500 at 3600 ram-speed+. On my coffee lake setup and my previous skylake setup tRFC was the second most impactful timing after CL. CR also has a bit of impact in many games.

Lowering tRFC from 420 to 350 on my coffee lake gave 3 ns lower latency in Aida64. Those of you with Micron can try getting as close as possible to 500. Going from 630 to 500 can have a significant impact.

 

[TheLostSwede]

TRFC has a large impact on latency and also gamingoerformance. Micron is worst at that timing. Samsung can often run below 300, Hynix below 400, but Micron often troubles with less than 500 at 3600 ram-speed+. On my coffee lake setup and my previous skylake setup tRFC was the second most impactful timing after CL. CR also has a bit of impact in many games.

Thanks for that insight. Something I really didn't know.

 

[Cowboystrekk]

Thanks for that insight. Something I really didn't know.

Glad to be of help If you read the ryzen calc review here at TPU you can compare the Hynix to Samsung setting. The main difference in timings between them is tRFC running a lot lower on B-die, which in some games can turn into several % performancedifference.

 

[TheLostSwede]

Not going to say it made wonders in AIDA64, but it seemingly made a small difference. It goes to show that some or the more advanced settings can make a difference though.

vs. previous result.

 

[Chomiq]

@TheLostSwede How's your IF ratio? 1:1 at 3800?

 

[TheLostSwede]

@TheLostSwede How your IF ratio? 1:1 at 3800?

Yes, it's 1:1 and it's 100% stable.
Maybe that's one advantage of the 3800X vs the 3700X?

Glad to be of help If you read the ryzen calc review here at TPU you can compare the Hynix to Samsung setting. The main difference in timings between them is tRFC running a lot lower on B-die, which in some games can turn into several % performancedifference.

This seems to potentially be the most important page in the review for people having issues.

AMD Ryzen Memory Tweaking & Overclocking Guide

Memory overclocking has a significant impact on performance of AMD Ryzen-powered machines, but the alleged complexity of memory tweaking on this platform, largely fueled by misinformation and lack of documentation, has kept some enthusiasts away from it. We want to change this.

www.techpowerup.com

 

[Cowboystrekk]

Not going to say it made wonders in AIDA64, but it seemingly made a small difference. It goes to show that some or the more advanced settings can make a difference though.

View attachment 131076

vs. previous result.

Have you tested the impact of lowering tRFC on Your system if you can do it without losing stability?

 

[TheLostSwede]

Have you tested the impact of lowering tRFC on Your system if you can do it without losing stability?

I just did, from 666 to 497, that was the difference in the two AIDA screenshots.

 

[Cowboystrekk]

Ah, I only saw that you changed 4th timing from 40 to 36 Not as much of a difference as I experienced, but a small improvement anyways. I bet that it will be more noticable in gaming. If you got a high end gpu and lower resolution a bit it will probably yield a small improvement.

 

[KhakiKukhi]

I can't even lower my Micron E-die from 630 to 500 without being unable to boot.

 

[Chomiq]

I can't even lower my Micron E-die from 630 to 500 without being unable to boot.

And if you set it to auto, what then?

 

[KhakiKukhi]

And if you set it to auto, what then?

Hmm... Lemme try and report back.

Woah.
Auto: 68.7ns
600: 70.1ns

 

[Chomiq]

Hmm... Lemme try and report back.

Woah.
Auto: 68.7ns
600: 70.1ns

And the actual value that was set from AUTO?

 

[Cowboystrekk]

Hmm... Lemme try and report back.

Woah.
Auto: 68.7ns
600: 70.1ns

What is value at auto? You can try 550, og 10 higher or lower if it Works or not

 

[gerardfraser]

Hmm... Lemme try and report back.

Now you finally able to run a test without errors after a week or more,your in a good place.OK now do not worry that one timing did not work yet.You wanted stability and no crashes with infinity fabric 1800.

Now to start on some of the other things I laid out in my little points.
Time to test with lower voltage on the DRAM First,screw the latency for now.So start knocking off voltage on the ram until error or failure.
When this is done I can help you get better results on the infinity fabric and latency.

Yes, it's 1:1 and it's 100% stable.
Maybe that's one advantage of the 3800X vs the 3700X?

There is no advantage over any of these CPU's like that on infinity fabric.My 2 x 3600X run 1900Mhz without problems.Just putting that out these.

https://i.postimg.cc/gmrnHwwz/Desktop-Screenshot-2019-09-03-15-33-36-28-2.png

 

[KhakiKukhi]

Hmmm... That's strange. The value for the auto setting is also 630.

Now you finally able to run a test without errors after a week or more,your in a good place.OK now do not worry that one timing did not work yet.You wanted stability and no crashes with infinity fabric 1800.

Now to start on some of the other things I laid out in my little points.
Time to test with lower voltage on the DRAM First,screw the latency for now.So start knocking off voltage on the ram until error or failure.
When this is done I can help you get better results on the infinity fabric and latency.



There is no advantage over any of these CPU's like that on infinity fabric.My 2 x 3600X run 1900Mhz without problems.Just putting that out these.

https://i.postimg.cc/gmrnHwwz/Desktop-Screenshot-2019-09-03-15-33-36-28-2.png

Okay, I'll try lowering the voltages. I'm currently stable on 1.440V.

 

[Chomiq]

Hmmm... That's strange. The value for the auto setting is also 630.


Okay, I'll try lowering the voltages. I'm currently stable on 1.440V.

Here's a SS from reddit, 3800 on E-die:

https://i.redd.it/tcpqmb735uc31.png

Stable at 1.41.

Guess I'll tinker with mine today.

 

[gerardfraser]

Hmmm... That's strange. The value for the auto setting is also 630.


Okay, I'll try lowering the voltages. I'm currently stable on 1.440V.

That is all good,now when you test you can be stable forever on memtest or similar but lower voltage on the RAM will have an effect on games so it would also be beneficial to test out games like Dues EX Mankind Divide/Anthem/Witcher 3 .

So if you start getting stuttering/hitching/crashes or just weird stuff you would need to add voltage to your RAM.

Anyway I am not trying to tell you how to do it,run your ram but I think with the settings you have now you change your CL14 to CL16 and DRAM Voltage can leave where ever you want 1.44 is fine and try DDR4 3800Mhz and Infinity fabric 1900.

I still suggest do it the proper way and take your time but it is your machine.

 

[KhakiKukhi]

That is all good,now when you test you can be stable forever on memtest or similar but lower voltage on the RAM will have an effect on games so it would also be beneficial to test out games like Dues EX Mankind Divide/Anthem/Witcher 3 .

So if you start getting stuttering/hitching/crashes or just weird stuff you would need to add voltage to your RAM.

Anyway I am not trying to tell you how to do it,run your ram but I think with the settings you have now you change your CL14 to CL16 and DRAM Voltage can leave where ever you want 1.44 is fine and try DDR4 3800Mhz and Infinity fabric 1900.

I still suggest do it the proper way and take your time but it is your machine.

Sorry, I'm unclear of what you want me to do.
You want me to clock my RAM to 3800 right?




This is what the Ryzen DRAM Calculator is showing me, CL14:

 

[TheLostSwede]

There is no advantage over any of these CPU's like that on infinity fabric.My 2 x 3600X run 1900Mhz without problems.Just putting that out these.

https://i.postimg.cc/gmrnHwwz/Desktop-Screenshot-2019-09-03-15-33-36-28-2.png

Well, not all CPU's will run IF at 1900MHz, so don't be that bold. I have a fair few friends working at various motherboard makers and not all the CPU's they've tested can run IF at 1900MHz and I would guess that's a lot more CPU's than what we've tested.

Sorry, I'm unclear of what you want me to do.
You want me to clock my RAM to 3800 right?

That's what he's suggesting. 3733 or 3800 would be the next things to try at this point, if you want to squeeze every bit of performance out of your RAM.
But as I also pointed out above, you most likely have to relax your timings to do so.

 

[KhakiKukhi]

you most likely have to relax your timings to do so.

Yeah, that's why I'm surprised at the CL14 the calculator told me.

 

[Chomiq]

Yeah, that's why I'm surprised at the CL14 the calculator told me.

That's cause you're using FAST instead of SAFE. SAFE should auto to CL16.

I stand corrected.

 

[KhakiKukhi]

That's cause you're using FAST instead of SAFE. SAFE should auto to CL16.

Believe it or not, I'm actually using SAFE, look at the top of the image.

View attachment 131099

That's cause you're using FAST instead of SAFE. SAFE should auto to CL16.

I stand corrected.

But I still think the calculator's wrong. 3800 at CL14 are you kidding me? That'd be the day.

Screw it, I'm gonna try it for the luls.

 

[Chomiq]

Believe it or not, I'm actually using SAFE, look at the top of the image.






But I still think the calculator's wrong. 3800 at CL14 are you kidding me? That'd be the day.

Screw it, I'm gonna try it for the luls.

Well you always have that reddit screen as reference for CL16 timings.

 

[gerardfraser]

Well, not all CPU's will run IF at 1900MHz, so don't be that bold.

Do you actually think ,I think that all Ryzen CPU'S can hit 1900Mhz.HMMMM interesting.

But I still think the calculator's wrong. 3800 at CL14 are you kidding me? That'd be the day.

It is possible and not a problem on ,now every Ram/Motherboard combo can not do this.I have 2 x 3600X that can.

Sorry, I'm unclear of what you want me to do.
You want me to clock my RAM to 3800 right?
This is what the Ryzen DRAM Calculator is showing me, CL14:

Sorry I am not trying to confuse you,
I suggest continue testing the voltage but if you want to just jump to test DDR4 @ 3800Mhz and infinity fabric to 1900Mhz you can if you want but you need to change what the calculator and your setting from CL14 to CL16.

Keep voltage at 1.44v on the DRAM and test.
So if you start getting stuttering/hitching/crashes or just weird stuff you would need to add voltage to your RAM.
Let us know what happens if you decide to jump ahead with higher settings.