Ryzen 7000 linux idle power, what's normal? High CPU PPT

Currently seeing ~100W full system idle power with a ryzen 7950x in eco mode, and 2 gpus. GPUs are reporting ~10W power each at idle.

lm_sensors is reporting ~50W package power under the CPU’s iGPU which seems high.

Is this expected? Anyone else running Linux on these able to share their power stats?

analyzing CPU 0:
  driver: amd-pstate
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 131 us
  hardware limits: 400 MHz - 5.88 GHz
  available cpufreq governors: performance schedutil
  current policy: frequency should be within 400 MHz and 5.88 GHz.
                  The governor "schedutil" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 2.74 GHz (asserted by call to kernel)
  boost state support:
    Supported: yes
    Active: yes
    AMD PSTATE Highest Performance: 166. Maximum Frequency: 5.88 GHz.
    AMD PSTATE Nominal Performance: 127. Nominal Frequency: 4.50 GHz.
    AMD PSTATE Lowest Non-linear Performance: 85. Lowest Non-linear Frequency: 3.01 GHz.
    AMD PSTATE Lowest Performance: 12. Lowest Frequency: 400 MHz.
# sensors output for CPU's iGPU
amdgpu-pci-6e00
Adapter: PCI adapter
vddgfx:        1.29 V  
vddnb:         1.00 V  
edge:         +46.0°C  
PPT:          58.08 W  
$ uname -a
Linux lun-hisame-nixos 6.0.2 #1-NixOS SMP PREEMPT_DYNAMIC Sat Oct 15 06:02:59 UTC 2022 x86_64 GNU/Linux
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I don’t have experience with the new Ryzen 7950, but the output for the IGP from my 5700G looks like

amdgpu-pci-0800
Adapter: PCI adapter
vddgfx: 949.00 mV
vddnb: 993.00 mV
edge: +30.0°C
PPT: 1000.00 uW

I’d say this is immature sensor software.

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Sensor seems to be close to correct given 100W total system power at the wall.

That or the x670e platform’s eating 50W.

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I do not think that there is anything wrong with the sensoring, high temperatures and high power consumption is the sad reality with the new Ryzen 7K platform - even @ idle. There are quite a lot of rumors that this is caused by a very high PPT and VCore, and that this may be fixed by lowering the core voltage without have a significant performance hit.

Good luck! :slight_smile:

Looks like this video has it at 42w cpu idle. then 2x 10w for your graphics cards, 5w per stick of ram and then the rest of the motherboard + psu inefficiency; 100w idle from the wall doesn’t really sound totally broken just not great

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Interesting. Thanks for sharing.

Well, that’s broken to me.

I appreciate high power consumption on load. Especially, if I can tune this with BIOS settings (PBO/CBO, ECO mode). But in reality most computer systems run idle most of the time. I have a hard requirement for that to be low - lower than last gen at least (AM4 isn’t that great in comparison to Intel since gen 6).

I hope that over the next few months we’ll see idle power consumption on AM5 come down.

Otherwise people may buy more AM4 …

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The only real benefit from AM5 is AFAIK PCIe 5 which may yield some respectable increments in data transfer rates for NVMe drives, up to three times faster than PCIe 4 (15GB/sec vs. 5GB/sec). For professionals working with video and photo processing, this may be appealing.

With the current platform prices and the insane power consumption combined with high electricity cost (currently €1/kWh in Denmark for some customers), the AM5 platform seems less appealing for the average user.

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… and even this is not a real benefit - yet. As far as I know there are no PCIe Gen5 expansion cards, and PCIe Gen 5 m.2 (or other format) SSDs still have to arrive.

The big curve ball could be RDNA3 / NAVI31 since that has support for PCIe 5 16x. But since NVIDIA’s 4000 series is not able to saturate PCIe 4, RDNA3’s support for PCIe 5 may be a fuzzy nothing burger.

SSD’s for PCIe 5 will eventually arrive, I’m quite sure of that. Samsung has flashed a 990 Pro with transfer rates of up to 13GB/sec read and 6,6GB/sec write.

@Danese, I can see your point about PCIe 5, but no one is talking about the limits of physical PCIe slots on the new motherboards. What I mean is that this time around, the motherboard manufacturers are trying to force more people to Threadripper Pro boards. On the new AM5 motherboards, I can’t see how you can have two graphics cards, an enterprise-level ethernet card, some other equipment you want to add for pass-through, and NVMe on the same physical system. My point is motherboard manufacturers are forcing people who want to mess with virtual machine pass-through to the Threadripper Pro system because that is the only current system that has enough physical PCIe slots.

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Hi,

Running Fedora 36, Radeon VII, and a 7950x with the “Balanced” Kernel setting:

analyzing CPU 0:
  driver: amd-pstate
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 131 us
  hardware limits: 400 MHz - 5.88 GHz
  available cpufreq governors: conservative ondemand userspace powersave performance schedutil
  current policy: frequency should be within 400 MHz and 5.88 GHz.
                  The governor "schedutil" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 400 MHz (asserted by call to kernel)
  boost state support:
    Supported: yes
    Active: yes
    AMD PSTATE Highest Performance: 166. Maximum Frequency: 5.88 GHz.
    AMD PSTATE Nominal Performance: 127. Nominal Frequency: 4.50 GHz.
    AMD PSTATE Lowest Non-linear Performance: 85. Lowest Non-linear Frequency: 3.01 GHz.
    AMD PSTATE Lowest Performance: 12. Lowest Frequency: 400 MHz.

and

amdgpu-pci-1a00
Adapter: PCI adapter
vddgfx:      729.00 mV 
vddnb:         1.24 V  
edge:         +41.0°C  
PPT:          31.14 W  

I followed the advice Wendell gave in one of the videos and use a negative PBO offset of -20. The video card is for compute only (and these numbers reflect no compute workload), using onboard gpu.

What is the “balanced” kernel setting?

It is a gnome setting that sets upper limits on the clocks for each core:

After more digging, I don’t think it is changing anything for Rhyzen as the min/max clock speed is always 400/5881 no matter the setting.

$ inxi -C
CPU:
  Info: 16-core model: AMD Ryzen 9 7950X bits: 64 type: MT MCP cache:
    L2: 16 MiB
  Speed (MHz): avg: 482 min/max: 400/5881 cores: 1: 400 2: 400 3: 400
    4: 400 5: 400 6: 400 7: 400 8: 400 9: 400 10: 400 11: 400 12: 3053 13: 400
    14: 400 15: 400 16: 400 17: 400 18: 400 19: 400 20: 400 21: 400 22: 400
    23: 400 24: 400 25: 400 26: 400 27: 400 28: 400 29: 400 30: 400 31: 400
    32: 400

Is that connected to powerprofilesctl?

$ powerprofilesctl
* balanced:
    Driver:     placeholder

  power-saver:
    Driver:     placeholder

If it’s changing that setting I think AM5 platform doesn’t have a driver for it.

I think it is, on an intel-based workstation at work, I get this:

$ powerprofilesctl
  performance:
    Driver:     intel_pstate
    Degraded:   no

* balanced:
    Driver:     intel_pstate

  power-saver:
    Driver:     intel_pstate

but on the amd platform, I get what you are getting (choosing balanced in gnome control panel):

$ powerprofilesctl
* balanced:
    Driver:     placeholder

  power-saver:
    Driver:     placeholder

The settings never change any of the clocks, you are right about the driver.

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One final piece of info.

Run sensors under idle:

amdgpu-pci-1a00
Adapter: PCI adapter
vddgfx:      734.00 mV 
vddnb:         1.24 V  
edge:         +42.0°C  
PPT:          31.10 W  

Run stressapptest -s 60 -M 64 -m 16 -C 16 -W and check sensors:

amdgpu-pci-1a00
Adapter: PCI adapter
vddgfx:        1.32 V  
vddnb:         1.24 V  
edge:         +48.0°C  
PPT:           5.11 W  

Real questions about what is being measured with PPT here.

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