x370 Taichi fans issues with 1.0.0.6a

My fans are not working right with the new bios, it keeps changing the speed up and down since the update.
Does anyone know a fix for it?

ramonsantana wrote: My fans are not working right with the new bios, it keeps changing the speed up and down since the update. Does anyone know a fix for it?

NOTE: All the information in this post is solely based upon my experience with my ASRock Ryzen board, which I have used since shortly after Ryzen processors were released. It is also is based upon the forum posts and information supplied by other ASRock Ryzen board users.

Sorry but this situation requires detailed explanation. If you don't care for the explanation, skip to FIX, below.

The basic reason for this, which seems to be consistent across all ASRock AM4 boards with the 3.00/AGESA 1.0.0.6a UEFI installed, is the temperature reading from the Ryzen processor used to control the fan's speed has changed. Specifically, any fan header that is configured to use the CPU temperature to change its speed will be significantly affected.

Have you ever looked at the H/W Monitoring screen in the UEFI? At the top it shows the CPU temperature reading. With earlier UEFI versions, the CPU temperature was in the mid 30's C. With the 3.00 UEFI, it is in the high 50's to low 60's C.

Ryzen processors report two CPU temperatures, called Tdie and Tctl. Tctl is the Tdie temperature + a 20° C offset. If Tdie is 30C, Tctl will be 50C, for example.

ASRock in earlier Ryzen UEFIs, seemed to be using a third temperature, apparently something like the old AMD CPU socket temperature (I'm calling it "socket temperature" simply as a name, it is NOT an official Ryzen AMD or ASRock term.)

This "socket temperature" is lower than Tdie, and does not increase very much from its idle temperature, or increase as quickly as the Tdie temperature does. It also never becomes as high as the Tdie temperature is. This temperature was reported in the UEFI, and also shown in the ASRock utilities such as F-Stream, A-Tuning, etc.

AFAIK, the pre-3.00 Ryzen UEFIs were using the "socket temperature" as the CPU temperature, which was used by the CPU fan header(s), and any other header configured to monitor the CPU temperature. The 3.00 UEFIs are now using the Tdie temperature for the fan headers that monitor the CPU temperature.

So while the socket temperature would usually vary from about 30C to 40C, Tdie will vary over a much larger range, 30C to 70C+.

Modern processors like AMD's Ryzen and Intel Kaby Lake will change their temperatures quickly and drastically from idle to even moderate load conditions. Quickly means in one second, and drastically means at least 20°C. That is, the Ryzen Tdie reading and the Intel core or CPU PECI reading.

That explains the general increase in fans speeds, and in the faster and slower fan speeds. If you use a monitoring program like HWiNFO64, you can see the Tdie temperature change quickly higher and lower, and the fan speeds with it. As the Ryzen CPU changes from idle to a loaded condition, its Tdie temperature changes, and depending upon which fan speed profiles you are using, the fan speeds along with it to varying degrees.

I am experiencing the same fan speed behavior with my ASRock X370 Killer SLI/ac board, with its 3.00 UEFI. Other ASRock Ryzen users are reporting the same thing.

Why was this change done? A significant number of ASRock Ryzen board users that were monitoring their Tdie temperatures noticed their CPU cooler's fan speed was not at the speed they expected/wanted for higher Tdie temperatures. They realized that Tdie was not being used by the UEFI's fan speed control features. Those users complained in this forum and to ASRock technical support.

So, the fans are actually working fine, and simply responding to the change in the different CPU temperature now used to control the fan speeds. Many people set the fan speeds to the maximum level that is not too loud to their ears, in the normal operation of the processor. Now that the fan speed control is changing the fan's speed more often, and to speeds beyond the noise comfort level, we are noticing that. While some may consider the fan speed control broken, it is really just different. Of course when it appears as a surprise without any warning, it's not a surprise that we might consider it to be not working right. I cannot blame anyone for feeling that way.

FIX
What is the fix? The fix is just an adjustment, and depends upon your personal usage of a PC, and what your priorities are.

If you want quiet, unchanging fan speeds and are not concerned with short term increases in CPU temperature, select the Silent fan profile. Or with other built in profiles, set any fan headers that can monitor the CPU or board to Motherboard. Or create a custom profile that runs your fans at a comfortable to your ear speed, and set the temperature range at that speed from 30C to 70 - 80C.

quicknick wrote: Thanks for the explanation, parsec. What about Silent profile, does it still use the socket sensor? Or the fans keep jumping up and down every second? Drastic changes in Tdie, as you said. To me, this change is enough reason not to update the bios. I'm very happy with the fan curves that I defined, it is true that they rev up with a slight delay but nothing to endanger the CPU. Would it be extremely hard to add an option in bios, to be able to choose between socket sensor and Tdie/Tctl? Or else, maybe something that makes the fans less jumpy - for example averaging the last 10 seconds of Tdie instead of reacting to sudden spikes.

Great suggestions, I made a more static choice by removing a fan controller from another workstation(my i7) and put it into my Ryzen 1800x workstation. It's the NZXT Sentry 3 and it can control my fans at a static level that prevents the drastic RPM changes that increase dba/noise.

I leave my fans alone most of the time and adjust them as needed. I recently added two Noctua NF-A14 IPPC 3000rpm fans that stay most of the time at %40(1400 rpm est.)

So you may want to try a fan controller if your budget allows. Mine is several years old but still works great, especially with the recently added 'mighty' Noctua fans.