Safe 3990X Overclocking?

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Hi,

I just bought a workstation dedicated to 3D graphic design rendering work, and I'm a bit frustrated because of my cpu current frequency: it's an AMD 3990X and its frequency is actually stuck at 3.1GHz which is not that bad, but way below what I was expecting.
I read on AMD website that this cpu has a "Max. Boost Clock of Up to 4.3GHz" ... so my question is: how can I achieve that?

I guess it has something to do with enabling PBO so I went into the BIOS, enabled it, set few parameters to the maximum allowed (Max freq offset: 200 MHz ...), but ... still, there's barely no difference whether it's on or off when running Cinebench R20 :( (score: 23700)

So I'd highly appreciate if you guys could tell me few hints on how to SAFELY go beyond the 3.1GHz frequency my cpu currently runs at. And by safely, I mean I want to set the frequency higher but not to a point where it can damage my cpu on the long term. This cpu is a costly one, and I want it to run safely for years to come :))

One small additional question, which I think is kind of related to the first one: CPU-Z x64 says my RAM frequency is 1333MHz. Is it normal? As it's RipJaws DDR4-3200?

Here is my machine specs:

* ASUS PRIME TRX40-PRO S
* AMD Ryzen Threadripper 3990X
* Noctua NH U14S TR4-SP3, push-pull configuration (with one additional fan)
* Case: Be quiet! Silent Base 802, with 5 x be quiet! Silent Wings 3 140mm Fans
* RAM: 128GB G.Skill Ripjaws V 3200MHz (4x32GB | 16-18-18-38)
* PSU: Corsair AX1600i
* MSI RTX 3060 Ventus 2X OC - 12GB

Thanks a lot in advance for your help, much appreciated,

Tim
 
Single core boost is 4.3ghz
Multicore is 3.45ghz.

Your ram is running at 2666mhz as its double data check xmp profile in the bios.
 
Thank you @mickyflinn

So why is my RAM running at 2666MHz when it's called "3200MHz"? Shouldn't it run at 3200MHz instead? I see in the BIOS I can set RAM frequency to 3200MHz (currently it is set to 'Auto'): is it safe if I do that?
And regarding the cpu, in the BIOS I see I can change the cpu core ratio: at the moment it's set to 31. But I can go for whatever value I want visibly. Should I set it to 43 instead so that I can achieve 4.3GHz single core boost? Is it safe?

Thanks a lot for your insight.
 
Thank you @mickyflinn

So why is my RAM running at 2666MHz when it's called "3200MHz"? Shouldn't it run at 3200MHz instead? I see in the BIOS I can set RAM frequency to 3200MHz (currently it is set to 'Auto'): is it safe if I do that?
And regarding the cpu, in the BIOS I see I can change the cpu core ratio: at the moment it's set to 31. But I can go for whatever value I want visibly. Should I set it to 43 instead so that I can achieve 4.3GHz single core boost? Is it safe?

Thanks a lot for your insight.
Motherboard has probablly default to that frequency you could try 3200mhz but it's not 100% gauranteed and you may have to drop back down.

Changing the multiplier to 43 will make it crash if set to all cores as that for one single core frequency l. I don't know a lot about ryzen settings but hopefully others may come along and help.
 
Thanks @mickyflinn, your explanations make perfect sense.

After having dived deeper in the BIOS settings, I realize how complex they are. For example I found different places where I can change the RAM frequency: under Advanced > AMD Overclocking > DDR and Infinity Fabric Frequency/Timings > DDR Frequency and Timings > DRAM Timing Configuration > Memory Clock Speed, and I can also change it under Ai Tweaker > Memory Frequency.
So it's pretty confusing, and I'm not sure how to proceed for a safe and effective overclocking as there are tons of obscure settings names.

Do you have any link to recommend? Any method on how to achieve decent overclocking of cpu and possibly RAM as well? I don't want to go insane on clocks, I just to make sure I get the most out of my machine and keep all components safe in the long term. I will definitely not go crazy by tweaking each and every BIOS settings.
 
Last edited:
@mickyflinn

I enabled XMP on my BIOS and now the RAM is running at 3200MHz :))

By playing with AMD Ryzen Master I managed to push the cpu frequency to 3.9 GHz by choosing the "Auto-OC" mode.

I launched Cinebench R20 and scored 28380 pts: a 20% performance gain compared to when the cpu was running at 3.1Ghz.
Here is what AMD Ryzen Master said while running Cinebench: CPU temp reached 95 deg Celsius (!), Peak speed 3,900 MHz, PPT hit 84% of 600W, CPU power hit 407W, SOC Power 37W, TDC (CPU) 93% of 400A and EDC (CPU) 100% of 470A.

It is a bit extreme and I don't want to run such high values on the long term.

So I'm now looking for a way to decrease a bit the frequency of the cpu but I don't know how to do that. I had a look at the "Manual" mode but honestly there are too many settings, I just don't know how to correctly set all of them.
 
For the 3900x, as long you have a decent cooler and decent airflow, you can leave PBO active, as long you manage the voltage. Here I use offset negative -0,1. Boost to 4.65 in most cores as single thread and 4.35 multi.
Temperatures never higher than 75C using any benchmark, and usually under 65C under normal load. Idle is on low 30's. Room at 24C
 
Thanks @mickyflinn

Actually I read this recent article https://www.cgdirector.com/amd-thre...wnsides_of_Switching_to_a_High-Core_Count_CPU and the guy says it's a bad idea to overclock the 3990X in case of professional workloads, which is my case (I do 3D graphic rendering).
So for now, I've set it up to "Auto OC" in Ryzen Master software and it seems just fine for my needs as in heavy single-core workloads the cpu now runs at 4.1 GHz, which is really good, and in heavy multi-core workloads, it runs at 3.1 GHz which is also good as it guarantee to not damage the cpu on the long term, which is what I want first.

That being said, I would like to push the cpu a little bit further in multi-core workloads as I still have room for it (temperature is only 65 deg C with 100% workload) but I still didn't figure out how to achieve that: how does Ryzen Master software work remains quite a mystery to me to be honnest. I don't clearly understand if it does change settings in the BIOS? Or is it just an "on-the-fly cpu settings tweak" taking place in Windows only?

@Drumroll , I'm quite impressed by your OC performance: how can I know if PBO is enabled or not? As in Rysen Master software I just see 3 settings and none of them is "PBO": I see "Default", "Auto-OC" (current), and "Manual" (from memory but I can't check right now as the machine is running a RAM test).

Is "Manual" mode what you call PBO? I tried to play a bit with it by very slightly increasing the CPU voltage and cpu frequency: the machine froze.

Thank you again for your support guys, really appreciated,
 
@OeufMayo_49

Ryzen master does change settings in the bios that's why you have to restart the of to take affect and load every time you boot up.

As for overclocking further this is where I sign off because I don't have any experience.

Good luck.
 
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