AMD Frequency Hardware Limits

Software & Operating Systems Linux
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1

Hi.

I have a problem on my manjaro system (Arch based) where tools such as cpupower the says the max cpu frequency is 3.5 GHz. And I was wondering how I could increase this as my 3950x has a max single core boost of 4.7. My behavior in windows was normal, and as intended by AMD. The command listed below says my hardware limitations are 2.2 GHz to 3.5GHz. If i use the Performance governor the clocks do go over 3.5 GHz, and up to about 4Ghz, but never above this.

So what I’m specifcally wondering; is there a way to make linux read a higher max cpu frequency, so i can use utility such as cpupower(-gui) to have more control over clock speeds?

$ cpupower frequency-info

analyzing CPU 0:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency:  Cannot determine or is not supported.
  hardware limits: 2.20 GHz - 3.50 GHz
  available frequency steps:  3.50 GHz, 2.80 GHz, 2.20 GHz
  available cpufreq governors: performance schedutil
  current policy: frequency should be within 2.20 GHz and 3.50 GHz.
                  The governor "schedutil" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 3.09 GHz (asserted by call to kernel)
  boost state support:
    Supported: yes
    Active: no

If needed; inxi -Fxz

System:    Kernel: 5.4.74-1-MANJARO x86_64 bits: 64 compiler: gcc v: 10.2.0 Desktop: KDE Plasma 5.20.2 Distro: Manjaro Linux 
Machine:   Type: Desktop Mobo: ASUSTeK model: ROG STRIX X570-E GAMING v: Rev X.0x serial: <filter> UEFI: American Megatrends 
           v: 1408 date: 04/01/2020 
CPU:       Info: 16-Core (2-Die) model: AMD Ryzen 9 3950X bits: 64 type: MT MCP MCM arch: Zen 2 L2 cache: 8192 KiB 
           flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm bogomips: 223649 
           Speed: 2677 MHz min/max: 2200/3500 MHz boost: enabled Core speeds (MHz): 1: 2677 2: 2054 3: 2193 4: 2196 5: 2195 
           6: 2195 7: 2195 8: 2195 9: 2621 10: 1990 11: 2148 12: 2171 13: 2046 14: 2031 15: 2045 16: 3744 17: 2008 18: 2195 
           19: 2192 20: 2195 21: 2195 22: 2196 23: 2195 24: 2062 25: 2196 26: 2195 27: 2007 28: 2041 29: 4520 30: 2035 
           31: 2196 32: 2195 
Graphics:  Device-1: NVIDIA TU104 [GeForce RTX 2080 Rev. A] vendor: ZOTAC driver: nvidia v: 450.80.02 bus ID: 0b:00.0 
           Device-2: NVIDIA GP104 [GeForce GTX 1080] vendor: ZOTAC driver: vfio-pci v: 0.2 bus ID: 0c:00.0 
           Device-3: Valve type: USB driver: uvcvideo bus ID: 8-3.1:5 
           Display: x11 server: X.Org 1.20.9 driver: vfio-pci note: display driver n/a FAILED: nvidia resolution: 
           1: 1920x1080~60Hz 2: 2560x1440 
           OpenGL: renderer: GeForce RTX 2080/PCIe/SSE2 v: 4.6.0 NVIDIA 450.80.02 direct render: Yes 
Audio:     Device-1: NVIDIA TU104 HD Audio vendor: ZOTAC driver: snd_hda_intel v: kernel bus ID: 0b:00.1 
           Device-2: NVIDIA GP104 High Definition Audio vendor: ZOTAC driver: vfio-pci v: 0.2 bus ID: 0c:00.1 
           Device-3: Advanced Micro Devices [AMD] Starship/Matisse HD Audio vendor: ASUSTeK driver: snd_hda_intel v: kernel 
           bus ID: 0e:00.4 
           Device-4: Texas Instruments PCM2902 Audio Codec type: USB driver: hid-generic,snd-usb-audio,usbhid bus ID: 7-4:8 
           Device-5: Valve Razer BlackWidow Chroma V2 type: USB driver: cdc_acm,hid-generic,usbhid bus ID: 7-3.3.3:19 
           Device-6: Valve type: USB driver: hid-generic,snd-usb-audio,usbhid 
           Device-7: SteelSeries ApS type: USB driver: hid-generic,snd-usb-audio,usbhid bus ID: 1-4.3:14 
           Sound Server: ALSA v: k5.4.74-1-MANJARO 
Network:   Device-1: Intel Wi-Fi 6 AX200 driver: iwlwifi v: kernel bus ID: 05:00.0 
           IF: wlp5s0 state: down mac: <filter> 
           Device-2: Realtek RTL8125 2.5GbE vendor: ASUSTeK driver: r8169 v: kernel port: d000 bus ID: 06:00.0 
           IF: enp6s0 state: up speed: 1000 Mbps duplex: full mac: <filter> 
           Device-3: Intel I211 Gigabit Network vendor: ASUSTeK driver: vfio-pci v: 0.2 port: c000 bus ID: 07:00.0 
           IF-ID-1: virbr0 state: down mac: <filter> 
           IF-ID-2: virbr0-nic state: down mac: <filter> 
Drives:    Local Storage: total: 3.41 TiB used: 1.27 TiB (37.1%) 
           ID-1: /dev/nvme0n1 vendor: Corsair model: Force MP600 size: 931.51 GiB 
           ID-2: /dev/nvme1n1 vendor: Samsung model: SSD 960 EVO 250GB size: 232.89 GiB 
           ID-3: /dev/sda vendor: Samsung model: SSD 850 EVO 250GB size: 232.89 GiB 
           ID-4: /dev/sdb vendor: Samsung model: SSD 850 EVO 250GB size: 232.89 GiB 
           ID-5: /dev/sdc vendor: Western Digital model: WD10EADS-00L5B1 size: 931.51 GiB 
           ID-6: /dev/sdd vendor: Western Digital model: WD1002FAEX-00Z3A0 size: 931.51 GiB 
Partition: ID-1: / size: 219.28 GiB used: 179.43 GiB (81.8%) fs: ext4 dev: /dev/nvme1n1p2 
Swap:      ID-1: swap-1 type: partition size: 8.80 GiB used: 218.2 MiB (2.4%) dev: /dev/nvme1n1p3 
Sensors:   System Temperatures: cpu: 63.8 C mobo: N/A gpu: nvidia temp: 36 C 
           Fan Speeds (RPM): N/A gpu: nvidia fan: 0% 
Info:      Processes: 550 Uptime: 4d 18h 21m Memory: 31.34 GiB used: 6.91 GiB (22.1%) Init: systemd Compilers: gcc: 10.2.0 
           clang: 10.0.1 Packages: 1749 Shell: Bash v: 5.0.18 inxi: 3.1.08
2

I am on a Ryzen 3900X and it boosts fine. Generally only to 4.4 GHz unless I boot it into single-user mode.

The file that controls this is /sys/devices/system/cpu/cpufreq/boost

As long as the ACPI frequency is set to maximum the CPU itself will go higher when it can. If you step down to 2.2 GHz then it won’t boost.

1 Like
3

Oh yeah more details. I don’t think Linux knows about favored cores. Ryzen CPUs have a few cores that can boost highest. The rest can’t. So, most of the time on Linux the kernel will assign a single task to the first core available and it is unlikely it will be the 4.7 GHz one.

At least that is how I understand it.