Ryzen and RAM timings

[Terry Rock]

"Play with those RAM timings fellas."
I've heard countless times that Ryzen...especially Zen 2 CPUs, respond extremely well to faster RAM.
I figured my system was already fast and very stable...no need to go tempting fate.
I took the 'hands-off' approach and didn't play around with it...that is, until today.
I had some time earlier and figured... "What's the worst that could happen...I'd probably have to reset a BIOS...big deal."
In just a few seconds, I took my inexpensive DDR4-3000 Ballistix Sport from the default CAS16-18-18-38 to CAS 15-17-17-38
The changes are staggering to say the least.
The bump in performance came with no stability issues...and all at the same default 1.35 volts.
The system ran great before but even I can see a noticeable difference.

Everything is smoother.
I just got finish doing the Silverstone wet weather challenge in ACC with the GTR Nismo....not one single stutter or micro-stutter...in over 20+ minutes of driving.

 

[Terry Rock]

Played around a bit more this morning with timings....got them down to CAS 14-17-17-36.
Full grid runs are a lot smoother...even during the formation lap
.

 

[Alex Townsend]

Any chance of some links or steps to take?
I have HyperX Fury 3200Mhz ram on its XMP profile 1.

I've never really bothered with RAM timings before as used to just set the XMP profile for my 3770k and have done with it.

 

[Terry Rock]

Any chance of some links or steps to take?
I have HyperX Fury 3200Mhz ram on its XMP profile 1.

I've never really bothered with RAM timings before as used to just set the XMP profile for my 3770k and have done with it.

PM sent.
I have XMP disabled and DRAM frequency entered manually...along with the recommended voltage.
My X470 Gaming Plus is extremely stable in that configuration.
Good luck.

 

[Alex Townsend]

Thanks for this. And the PM, I've been watching and reading and feel like I've just opened a big can of worms...
Mind = blown, so may take me a while as I'm one of those people that need to know what I'm changing and why... its gonna be a long couple of weeks of study on this topic.
Then I need to work out what all this overclocking on Ryzen malarkey is about... intel was so easy

 

[RobertR1]

Here's probably the best RAM tuning guide that applies to both intel and AMD: https://github.com/integralfx/MemTestHelper/blob/master/DDR4 OC Guide.md

If you want the absolute best RAM performance:
- B-Die
- Up voltages (read guide for ranges)
- Match your FLCK and mem frequency to a 1:1 ration
- Lower your primary timings to the lowest they will go
- Do your secondaries
- Do your tertiaries
- Use notepad to track changes and test in between changes

Can be very quick to very long depending on if you want to every settings at it's lowest possible.

 

[John-Eric Saxén]

Tweaking of RAM timings gives very little gain these days. It used to be a big thing 10 years ago, but these days frequency (aka bandwidth) is really what you should focus on. Also the relative gain going from CAS 16 to 15 is only 6% improvement in latency, whereas in DDR3 days going one tier lower from CAS 9 to 8 resulted in an 11% improvement.

 

[RobertR1]

Tweaking of RAM timings gives very little gain these days. It used to be a big thing 10 years ago, but these days frequency (aka bandwidth) is really what you should focus on. Also the relative gain going from CAS 16 to 15 is only 6% improvement in latency, whereas in DDR3 days going one tier lower from CAS 9 to 8 resulted in an 11% improvement.

If you're cpu limited, then the RAM tuning has notable benefits. More so if you manually tighten your timings.

That's one example. Others have done similar content you can search for.

I would take tight timings over loose one with more bandwidth anyday esp on Ryzen where breaking the FCLK and Mem clock is a major latency hit. .

 

[RasmusP]

It used to be a big thing 10 years ago

And it is again now for ryzen CPUs!
For the Intels it's not that important but for the modern AMD CPUs it's a big thing to consider and spend some time with!

 

[Terry Rock]

Minus the Youtube induced hitching...(not there in the actual replay)...this is the kind of game-play I'm getting with the new timings.
The additional smoothness and speed are noticeable.

 

[Alex Townsend]

Just a quick question this, would you sort your RAM timings first, and then look at giving the CPU an OC too, or do you get the CPU boosting properly first, then sort the RAM timings?
Got a feeling they are tied together in some way but wanted to get a handle on what to do first.
Also, any good tips on overclocking these things?
Some say they use Ryzen Master whereas others cant stand the idea of it and recommend going into the BIOS just as we used to with Intel...

 

[Terry Rock]

Get the CPU working stable before doing anything with RAM.
I haven't done any manual overclocking with my 3600X.
I prefer to let the boost clocks ramp up automatically as needed.
The thing runs so well at the default clocks that all I did was tighten the memory timings after verifying no memory errors in Memtest..

 

[John-Eric Saxén]

Minus the Youtube induced hitching...(not there in the actual replay)...this is the kind of game-play I'm getting with the new timings.
The additional smoothness and speed are noticeable.

No offense, but how are we supposed to judge the smoothness from a YouTube video exported at 30 FPS? With 30 FPS export anything will look smooth. What I would be interested in is numbers, some basic min/max/avg or whatever is possible to objectively see the difference.

I still think you'll likely get better smoothness by overclocking RAM frequency instead of timings. Also frequency and timings are two sides of a coin, with highest possible frequency you have to loosen the timings a bit and vice versa.

 

[Terry Rock]

No offense, but how are we supposed to judge the smoothness from a YouTube video exported at 30 FPS? With 30 FPS export anything will look smooth. What I would be interested in is numbers, some basic min/max/avg or whatever is possible to objectively see the difference.

I still think you'll likely get better smoothness by overclocking RAM frequency instead of timings. Also frequency and timings are two sides of a coin, with highest possible frequency you have to loosen the timings a bit and vice versa.

It has already been proven in most cases, that manually overclocking Ryzen can lead to less performance.
I already have great gaming experiences with my settings.
Again...it is an individual preference.
I'm not for or against others doing either.

 

[Durge Driven]

I have 3900X + B450 board + 3600 C18 does 4350MHz @1.25
If I use precision is slower, higher voltage hotter etc etc where manual it runs 100%
It is down to MSI bios hopefully fix issues with next my opinion not likely
The X570 board and memory I really wanted was $600AU dearer then what I ended up with

$600AU = better gains jumping from 2080 to 2080ti ...no matter what chipset/ram speed/timings are

P.S. any gains for free are good value of course

 

[Durge Driven]

So what do I want to do higher clock or lower timings ?
At the moment running in B450 Carbon @ XMP 1.4v

I know I said $600 is better spent on GPU but circumstances changed
Gigabyte X570 Pro Wifi dropped $60 and the good ram $70
I want cheap 2nd tower to run this Summer so using my B450, memory and AMD 3200G
Be slow encoding and other things but better then using good tower all summer

Even stock with liquid the 3900X will be too hot for full load ( 40c+ days and very hot nights )

Can't afford Air Cond. just for PC

 

[RobertR1]

If you're on ryzen, you need to make sure your mem clock doesn't exceed your fabric clock (fclk). You need to maintain a 1:1 ratio. Going to a 1:2 divider is never worth it due to the latency hit you pick up.

So if your FLCK is 1800, you want your ram to be 1800 (effective 3600mhz) due to DDR. If FLCK = 1900mhz than RAM needs to be 3800mhz effective.

Once you have 1:1 done, then tighten your primary, secondary and tertiary timings in that sequence.

 

[Durge Driven]

Thanks Robert
Yes mem/fabric 1:1

 

[F1Aussie]

My neo 3600 ram is stock at 16 16 16 36 and the gameplay I get in Sims us the smoothest I have ever had

 

[Terry Rock]

After examining Zen2 architecture and getting a lesson on CCXs and how they work,, I decided to do some additional testing.
During the R20 single core test with core boosting done per CCX basis...(as opposed to all clocks), I found that max scores were higher.
My 3600X reported a score of 505 single core and 3692 in multi core test.
This number was consistent over multiple test...(three single core and three multi core test).
The max core clock was (in order of cores) 0=4375, 1=4350, 2=4350, 3=4400, 4=4400, 5=4400.
Logic suggest that if the cores on the two CCX units are in numerical order, then three cores on a single CCX (in my case) are faster than the other.
With the way that the latest version of Windows 10 does pinning to the fastest cores, then single core applications may be able to take advantage of this configuration.
The OS calling on the cores capable of the highest clocks.
With 1.0.0.4 there is a setting in the BIOS to boost on an ALL core or a CCX basis.
Can somebody else verify this and post findings?