A friend and I are building roughly the same PC and we probably overdid it by buying DDR4-4000 memory, did we?!

Hello everyone,

this is my first post here and I was not sure whether to post this under “Motherboards” or here so please just move it if need be.

So a friend and I are building a new PC that has the same specs:

Case: bequiet! Dark Base Pro 900 rev2
CPU: Him: Ryzen 9 5900X / Me: Ryzen 9 5950X
PSU: bequiet! Straight Power 11 850W
CPU-Cooler: bequiet! Dark Rock TF
GPU: when availabe probably the Radeon 6800XT (Big Navi)
M.2 SSD: Samsung 970 Evo (PCI4 was overkill in our humble opinions)

Now comes the part where we overdid due to an article in a German computer magazine I misinterpreted. I would recall it as stating “4000Mhz memory is the new sweet spot for the new Zen3 CPUs as compared to what 3600Mhz was for the Zen2 CPUs”. So we bought:

TridentZ 32GB DDR4-4000 CL19-19-19-39

So when the Zen3 got announced and I saw Wendell’s last video on Level1Linux on YouTube and I heard that he barely got DDR4-4000 working with “some fiddling” I was like “damn I should have waited for the detailed reports about real-world Zen3 systems”. Worse: “You should go with 3600Mhz with CL16 or CL14 timings” kinda got me panicking and feel a lot of remorse on spending 390€ on the memory.

So then I went on the allknowing interwebs, but could not find a good guide explaining the loops you need to jump through to get 4000Mhz memory working.

**So finally and also TL;DR: **
What do we need to do to get our DDR4-4000Mhz memory working on the ASUS TUF GAMING X570-Pro with a 5900X/5950X?

Since the CPUs are still not there and it will be a while until we can buy them (I bet the Big Navis will bring us the fourth Hardware paper launch this year sigh) I am actually pretty patient and thankfully await your wisdom and advice forum. Thanks in advance :)!

EDIT: He will be using the latest Windows 10 Build, and I will be using Artix Linux with kernel 5.10


To get it working, lower the clock speed on the RAM to 3600 or even 2666. That way your systems are at least usable, just not the most efficient in cost/performance. Alternatively, load the “safe settings” option in the BIOS and if that works, try the “optimum performance” option. Keep the XMP profile disabled. (mind, settings may have a different name, but you’ll get the drift :wink: )


Just enable the D.O.C.P. or whatever asus shenanigans and then dial it back if you need to by 200-400mhz and tighten timings by 1.

People seem to be under this notion that they have to get IF clocks as high as possible but timings are also very important. Its all well and good to get data in and out of cache as fast as possible but eventually you need to hit ram and then timings matter just as much as frequency for overall bandwidth.


Keep in mind that memory compatibility generally improves with UEFI updates, so max memory speed should if anything improve in the future. Though this is a very mature socket, and AFAIK the IO controller that handles the ram is the same as ryzen 3000, so I wouldn’t expect as much improvement.

Even if you buy 4000mhz ram and it does not work at 4000mhz out of the box, you can run it at a slower speed, like 3600mhz. You will just probably have to punch in the speed manually instead of selecting the AMP (AMD’s name for XMP) profile. A slower speed may also allow you to get tighter timings than advertised for the 4000mhz speed, which will improve performance.

By default it will run at a slower speed (IDK for 5000 what the default is), maybe 3200 or 2666 or something. To get the full speed, you have to manually set it in the settings.


Hey guys thanks a lot for your answers.

So I basically either go down to 3600 and set the timing to 18


I type in 4000 (and the timings also?) manually?

(I never have dealt with RAM settings ever in my life. I just stick RAM on my board and then do not think about it until the next build)

And another question since someone already mentioned Infinity Fabric (IF): What is the IF? And why does the only advice I could find on this issue was that I need to crack the IF frequency up to 2000Mhz? And why do you guys do NOT recommend that particularly?

Thanks again :slight_smile:


My suggestion is go to youtube and search how to overclock ram on ryzen x570 mbs. Watch as many sources as you can find.

Seems like you have some research you need to do. Or return the 4000 ram and purchase 3600 cl 16 from the qvl list.

I just remembered why I am not overly fond of asus mb support.

While ram overclocking is much easier these days … You still have to work for it. Do your research there is plenty of reference material on youtube. Come back when you have specific questions. We will be happy to help but first you need to get to first base.

These guys sometimes forget that not everyone has their level of experience. Follow my recommendations and comeback with your questions. We should be able to help you get even further along.


Honestly, I would not type in all settings manually, but select XMP and then change the clock speed and adjust timings.

Also, I wouldn’t set it to 3600 but I’d go for 3800 instead and see how low I can get the timings. The RAM calculator linked above by @thevillageidiot will help you in that regard.

Furthermore, you can still try XMP and see if you board manages DDR4 4000 with IF 2000MHz. However, be careful that when you activate XMP your RAM speed will most certainly be 4000MHz even if it does not work. You need to confirm that IF is at 2000MHz. If IF 2000 doesn’t work, set your memory to 3800 and IF to 1900.

I overdid it as well and bought this kit:

But hey, at least it’s dual rank, otherwise we would have to use 4 sticks^^
(Check GamersNexus’ video for that or Wendell’s upcoming video.)


And since it does not yet seem to be said. Azulath has it, sorry.

Just for shits and giggles, when you get it all together, just turn on the XMP/A-XMP/AMP/D.O.C.P. or whatever it happens to be called for you and see if it "Just Works"™

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Hiting 2000 1:1 . do it dont whine !

More power:P

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Wow this forum is constructive and supportive. Thanks so much for all you answers.

So I think I did not overread it, so I have to ask again sorry. What is IF and specifically why is it important to bring it to 2000Mhz?

Infinity Fabric is the interconnect between the Ryzen Chiplet Cores and the Memory/IO controller if I remember correctly.

The reason for it being 2000MHz to.the RAMs 4000MHz is that DDR stands for Double Data Rate so your 4000MHz ram is issuing two commands every cycle so its “actual” speed is 2000MHz.

Ryzen works at peak effecincy for memory transfers and reads when both the Infinity Fabric and the Memory are at equal speed as it can send the instruction straight through with no wait.

So no matter what DDR memory speed you end up using it is optimal to have the Infinity Fabric speed at exactly half of that.

3600MHz RAM = 1800MHz IF
3800MHz RAM = 1900MHz IF
4000MHz RAM = 2000MHz IF


Nice and easy explanation, great.

So on an ASUS GAMING X570-PRO is it known whether or not an IF of 2000Mhz is likely to work? BTW: Of course I will use FlashBack to flash the newest AGESA before even trying anything! From what I read it somehow read as if you “need to be lucky” kind of like that it depends on the quality of silicon you happened to get when you bought your specific product.

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The speed is not down to the motherboard, it is the CPU that is the deciding part. So yeah it is “need to be lucky” with the silicon quality thing.

That said memory stability and speed improvements have happened with pretty much ever version of Ryzen in some from through BIOS updates, so even if it does not work right away, it may eventually.

The saving grace may be that AMD did say in a slide before 5000’s launch that 4000MHz was the new top speed, so hopefully if it does not work right away, it should work later on.

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A few reviews I’ve seen agree with this. For many Zen3 CPUs the highest you can get the Infinity Fabric is 1900 which is one half 3800. You don’t really want to use a desynchronized IF speed if you can help it.

And to hit 3800 on RAM you need to buy 4,000 since no one seems to sell a 3800 rating.

And of course you might get lucky and be able to run IF at 2000.

G.Skill and Corsair do (the thumbnail appears to be German, but the site is in English):

If it doesn’t work, you can downclock.

The only way you can over do it is if you spent so much money it puts you in the gutter.

It likely does not make much sense to go much higher then 3600mhz / 1800mhz IF CL16.
Everything above that you will likely see diminishing returns.
4000mhz might be possible if you get a good cpu.
But i kinda expect that most of them will do 3800mhz ish / 1900mhz IF


Another good addition to this is that any benefit you see with higher IF will not be realized in most real world scenarios. In day-to-day PC usage, I’ve yet to see any serious and tangible benefits from going beyond 1800mhz IF. Benchmarks be damned, if it doesn’t improve much in real-world usage, I’d rather favor stability and focus on optimizing the timings at 1800.

Judging by the timings, overflyer and his buddy obviously got good sticks. I’d bet he could do 3600 CL16 (16/16/16/36) at a minimum, maybe even lower. That’s nice and speedy, and easy to attain without sacrificing stability.

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