Overclocking Ryzen, while CnQ Turned on!

2017. 10. 20. 11:26

It is a part of the world's Ryzen users to wonder about, and there are many people who do not yet know it, so I write in English.

Nessesity

CnQ or SS is a technology that saves power by lowering voltage and clock. Since power consumption is proportional to the clock and is proportional to the square of the voltage, when CnQ is used, it must be lowered to not only the clock but also the voltage.
Most overclockers do not use Cool'n'Quiet or Speed ​​Step. This is because overclocking is for better performance, but using CnQ or SS will reduce performance.
However, if you can fine-tune the power options in Windows, you can achieve maximum performance with CnQ or SS. The performance is lower than when you do not use CnQ or SS, but you can enjoy the effect of overclocking and the power saving / thermal management effect of CnQ or SS when not using for a long time. Moreover, in today's 8-core systems, there may be cores that do not work according to the game's optimization level. You can save power even during the game.
I tend to turn on the computer for a long time, so I prefer to turn on CnQ or SS even if I overclock it.

Intel

But there is a problem. I do not know if this is a problem with Ryzen, but I could not turn on CnQ just like Intel.
Intel was not difficult to overclock while SS turned on.

If you set the CPU Vcore Voltage Mode to Adaptive Mode like in the above picture, the overclock will be set to the user defined voltage only at the highest clock, and the lower clocks where Speed Step operates, the default voltage is applied.

Ryzen

But Ryzen is different.

In the above picture, only the Auto, Offset Mode, and Fixed Mode are available in CPU Vcore Volate setting.

With Offset Mode, the voltage compensation(Offset-ting) will be applied even at low clocks where CnQ is operates. If you overclock at a high voltage, the voltage will be high even if CnQ is activated.

Fortunately, Ryzen can change each Pstate.

Here you only need is to increase the voltage and clock of the highest clock(Pstate0). This is not difficult because it is the same process as general overclocks that do not use CnQ.

I wouldn't write post if turning CnQ on is finished like this.

The problem is that when changing Pstate0 in the BIOS, the Pstate0 state will not be reached if it is higher than the "default voltage".

When CnQ is off, it is ok to raise the voltage of Pstate0 at random, but when CnQ is on, if the voltage is higher than the "default voltage", the CPU state transition will not made to the Pstate.

"Default voltage" for Ryzen 1700 is 1.18750 V.
A 3.6Ghz model, such as 1600 or 1700X, is supposed to be 1.35V.

So, in Pstate0, set to the "defaul voltage". In Offset Mode, increase the overall voltage to increase the voltage of Pstate0.

It then decrease the voltage of the other Pstate to make it the original voltage.

Full Work

So I will try to CnQ to fully work with using both voltage offset and custom Pstates functions.

Not surprisingly, overclocking stabilization should be done with SS or CnQ turned off, whether Intel or AMD.

Remember tabilized values. My Ryzen was stabilized at the clock of 3.775Ghz at 1.3V.

Overclock

Now, go to the Custom Pstates settings in Bios.

The voltage I need is 1.3V, but I set a voltage to the "default voltage" which is 1.18750V. I need additional 0.11250V to stabilize the CPU.

Now, Compensate(Offset) Voltage.

Set the voltage here to Offset Mode and add 0.11250 voltage. Now Pstate0 is 3.3775Ghz and is 1.3V

Change voltage of other Pstates.

Now re-compensate(re-offset) the voltage at the lower clock which CnQ is operates. Enter the Custom Pstates setup screen again.

Here, subtracts the voltage of Pstate1 and Pstate2 by 0.11250.

  • In my case I overclocked Pstate1. and I undervolted Pstate2.

  • 3.6Ghz models, 4.0Ghz models have different defaults for Pstate1 and Pstate2.

  • Therefore, do not compare with my clock / voltage.

This will increase the voltage only at the maximum clock while using CnQ.

Wrap-Up

As I mentioned in the introduction, there are performance differences depending on power options.

Refer to the following article to minimize the performance degradation(Korean only)

Windows 10 코어파킹 활성화 하기(activate Windows 10 Core Parking)

Windows 10 코어파킹 설정 값 같이 보기(See My Core Parking Settings)

라이젠, 무작정 따라하는 최적화(Ryzen Optimizing Guide)

AMD's motherboards include AMD Generic Encapsulated System Architecture (AGESA) software in the Bios.
In the Custom Pstates setting, it is an option of AGESA. If it is higher than the basic voltage of the CPU, it will not reach to that state. But think about whether it is possible to give a higher voltage by using offset because it is a voltage control option of motherboard itself. So there is separate software for the CPU in Bios, which seems to work separately from the mainboard Bios software. This is my guess, but it seems to be the most reasonable guess.

If the task manager displays the clock set by Pstate0 at the "Base speed", but the CPU does not actually change the state to the Pstate0 while heavy loading, then should follow the above steps.

The Custom Pstates function is included in all x370 and b350 boards because it is an AGESA function(I guess), and you should check the a320 board.
Offset Mode is definitely supported on Asrock and Asus boards.
Gigabyte has a feature called Dynamic Vcore. It seems to be the same function.

Biostar has comfirmed that is does not support Offset Mode.

Other manufacturers need confirmation.

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