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RAM overcloking on ZEN 3

Dux

Joined
May 17, 2016
Messages
511 (0.15/day)
I had ZEN 2 CPU. Ryzen 5 3600. And i could overclock my RAM to 3800MHz and get 1900MHz infinity clock with stable 1:1 ratio with memory controller clock.
Now i have ZEN 3 Ryzen 9 5900X. So since AMD promised increase of infinity fabric clock to 2000MHz, i decided to OC my RAM to 4000MHz.
I OC'ed it no problem. But i was suprised when i saw in OCCT that my FCLK was just 1800MHZ and UCLK was 1000MHz. So i did some googling and found out that PC gamer also had same results. They contacted AMD, and AMD replied that this will come with later BIOS updates. So i am disappointed that they said at that launch event how memory clock was increased to 2000MHz. So sick of being served bullshit from AMD,intel and Nvidia. Can't anyone tell truth any more? There always must be some bullshit and half truths. :mad:

Infinity fabric at the moment goes to 1800MHz. So i had to set my RAM to 3600MHz to get 1:1 ratio FCLK-UCLK. So i actually had tp lower RAM frequency from 3800MHz on ZEN 2 to 3600MHz on ZEN 3. Not 4000MHz like Lisa said in presentation.
Captures.JPG

4.JPG

Everything above 3600MHz RAM speed increases latency on ZEN 3 at the moment.

uu.JPG
 
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They didn't promise 2000mhz IF. 3200mhz is still the official specification.
 
Yes they did. Did you read the article i linked?
View attachment 175163

That's not a specification. 3800mhz was NEVER promised either. And FYI, 3800mhz ram required one to fiddle with settings to make it work. Nothing has changed in that respect. Cliffnotes, you are on your own when overclocking the IF, which is what you are doing.
 
That's not a specification. 3800mhz was NEVER promised either. And FYI, 3800mhz ram required one to fiddle with settings to make it work. Nothing has changed in that respect. Cliffnotes, you are on your own when overclocking the IF, which is what you are doing.
LOL. :laugh:
 
I like the highlighted good luck


once the new BIOS gets here in a couple months, 4000 ram will be easy to get for all of us with B-Die I expect.

just be patient
 
I slept over it and decided to try again. This time i didn't let BIOS do what it wants and set the Fclk manually to 2000MHz and FCLK-memclk from auto to FCLK=memclk.
I had to raise voltage of my RAM slightly from 1.4 to 1.41V for stability and loosen the latencies a bit from what i had on 3800MHz, from 16,19,19,39 to 16,20,20,40.
I don't have some special fancy RAM. Crucial Ballistix Sport with micron chips. So i'm happy i managed to get here at all.

ff.JPG

fff.JPG
 
Yes they did. Did you read the article i linked?
View attachment 175163
I presume English isn't your first language?
There was no such thing promised there.
Just as 3800MHz was not promised on the 3000-series.
It's a best case scenario.
I'd suggest you read this, which contains a very lengthy explanation from AMD about RAM, among other things.
 
I presume eye sight isn't your best thing. Or hearing. Since Lisa Su said at ZEN 3 reveal what i highlighted in that picture i posted. 3800 was sweet spot for ZEN 2. 1900MHz infinity fabric clock was maximum. 2000MHz for Zen 3. All in that picture i posted. Some users couldn't get to 1900MHz stable. Were unlucky with bad samples. But that was the official maximum.
 
I presume eye sight isn't your best thing. Or hearing. Since Lisa Su said at ZEN 3 reveal what i highlighted in that picture i posted. 3800 was sweet spot for ZEN 2.
3600* was the sweet spot. This puts the IF at 1800MHz. 3800MHz (1900MHz IF) was maximum, and not all chips got there. 3800 was in no way, shape or form the sweet spot.

2000MHz for Zen 3. All in that picture i posted. Some users couldn't get to 1900MHz stable. Were unlucky with bad samples. But that was the official maximum.
Official maximum, but not guaranteed. Just like 1900 IF wasn't guaranteed on Zen 2 either, and a lot of Zen 2 chips didn't get to 1900. The slide even says "Good luck", implying you have to be lucky to get a 2000MHz IF clock. No, not bad samples, just not as good as others. The majority of chips probably didn't hit 1900MHz, as the majority sold was 3600 which is a lower binned chip than the ones higher up in the stack.

I think this is a case of you not grossly misunderstanding AMD's messaging. To everybody else however, this is pretty obvious.
 
I presume English isn't your first language?
There was no such thing promised there.
Just as 3800MHz was not promised on the 3000-series.
It's a best case scenario.
I'd suggest you read this, which contains a very lengthy explanation from AMD about RAM, among other things.

It's like trying to convince the crazy that they're not. Best to leave alone :P
 
OC-ing isn't for you guys. Just leave everything on default in BIOS and you're good to go. I'll always search for that maximum. Over & out.
Would you be unhappy if you bought a 10900K and couldn't get a 6GHz all-core?

"B-b-but all the XOC'ers can get it, so i-i-it's the maximum, so why can't I?"
 
I presume eye sight isn't your best thing. Or hearing. Since Lisa Su said at ZEN 3 reveal what i highlighted in that picture i posted. 3800 was sweet spot for ZEN 2. 1900MHz infinity fabric clock was maximum. 2000MHz for Zen 3. All in that picture i posted. Some users couldn't get to 1900MHz stable. Were unlucky with bad samples. But that was the official maximum.
Again, no. I don't know where this is coming from.
Image below is from the Ryzen 3000-series launch.
Sweet spot is 3600MHz.
In the early days, you were lucky to hit 3600MHz as the AGESA and UEFI releases were that bad.
3800MHz isn't happening on all chips even today. Plenty of people here can't get above 3733MHz.
So no, 3800MHz is NOT the sweet spot for the 5000-series and I have no idea why people believe this.
Also, did you fail maths class? 1900x2 =3800...

This is from AMD's Robert Hallock, who should know a thing or two about it.
What is the fastest possible RAM you can run with 1:1 fclk?

DDR4-4000. 2000MHz fclk is to the Ryzen 5000 Series what 1900MHz fclk was to the Ryzen 3000 Series. Many samples can do it, but not all. In upcoming AGESAs, we will be implementing additional tuning that will make reaching 2000MHz easier. This is not a guarantee. There is no “safe bet” that your CPU will reach this frequecy. But don’t be surprised to see a bunch of people bringing that magical 2000MHz fclk home with DDR4-4000.

Okay, so what’s the best price/performance?

DDR4-3600 continues to be a “sweet spot.” The kits are inexpensive, widely available, perform well, and have good compatibility. Is it the best in every category? No, but that’s not what the sweet spot is. 3600 is a good bet because it’s a good value in perf/$ for someone who wants to plug and play. Is it the best possible performance? No. Is it close? Yes, and without tinkering.

memory1.jpg


And considering Hardware Unboxed can't hit 2000MHz IF, I don't think "we are doing overclocking wrong". :rolleyes:
Besides, I thinks I have miles more experience with testing computers than you do, since I did it as a living.

 
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Again, no. I don't know where this is coming from.
Image below is from the Ryzen 3000-series launch.
Sweet spot is 3600MHz.
She did say sweet spot at launch, I also remember seeing that during the live (pre-recorded?) stream. What she probably meant that 4000MHz (like 3800MHz on zen2) is doable on zen3 & 1:1 ratio between FCLK, memclk should make it an optimal setup.
 
4000MHz on RAM. 2000MHz FCLK in 1:1 ratio with UCLK. CL15,19,19,39 with 1.44V. Current result. Will continue to fine tune. I haven't even touched sub timings yet. Gonna do that next.
 
The latency matters as well so I'll personally pick a 3200mhz with cl14 rather than a 3600mhz with cl16 or cl18 because in real world tests they both will give you the same results and you can over clock the 3200mhz to 3600mhz or possibly higher if you reall want
Depends on the price. You can do the opposite and get higher spec ram and just lower clocks which would allow you to run tighter timings ;) I'm running 3800 CL16 right now, with optimized sub timings, if needed, lets say because of higher FCLK instability, I can drop to 3200 CL12 or try for 4000 CL16, or try to optimize 3800 and drop from CL16 to CL15 or even CL14 if memory cooling allows.
With good 3200 CL14 kit you can try to the same ;) just pick what's cheaper.

4000MHz on RAM. 2000MHz FCLK in 1:1 ratio with UCLK. CL15,19,19,39 with 1.44V. Current result. Will continue to fine tune. I haven't even touched sub timings yet. Gonna do that next.
Do you actually see performance increase with these settings? No WHEA errors while running heavier loads? I tend to use Geekbench for memory OC to see if new setting gave me anything. In my case FCLK 2000 gave so many WHEA errors that performance was terrible, way lower than FCLK 1900.
 
Do you actually see performance increase with these settings? No WHEA errors while running heavier loads? I tend to use Geekbench for memory OC to see if new setting gave me anything. In my case FCLK 2000 gave so many WHEA errors that performance was terrible, way lower than FCLK 1900.
I just run Deus EX: Mankind divided bench for gaming performance gains. 720P, everything on lowest settings. RAM on default= 205fps avg. 3800MHz CL16 = 240fps avg. 4000Mhz CL15 = 250fps avg. I don't get any errors while testing with anything. I use OCCT and Aida64 memory stress tests
 
I just run Deus EX: Mankind divided bench for gaming performance gains. 720P, everything on lowest settings. RAM on default= 205fps avg. 3800MHz CL16 = 240fps avg. 4000Mhz CL15 = 250fps avg. I don't get any errors while testing with anything. I use OCCT and Aida64 memory stress tests
Great results then ;) I hope that next bios allows me to push for higher FCLK
 
I know Im late to this but good luck means luck or unlucky. AFAIK, FCLK oc to even higher 1900mhz is depend on processor Memory controller. Ive seen some ryzen 5000 series able to achive that. But some scenario occur where fclk 1900 but the mclk and uclk at 4000mhz is have better performance. I see it on Buildzoid overclocking on his youtube channel.
 
@DuxCro try running HwInfo64 and tell me if You have WHEA Errors (CPU Bus Interconnect errors) after making some read tests in AIDA64 and how many errors are there. I tend to believe that your system is not so stable as You might think, as the new AGESA can enable bigger IF, but with unstable results. The system can pass memory tests, can be stable for a while, then randomly it will get BSOD.
 
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