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** Changed in: linux (Ubuntu)
       Status: New => Confirmed

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  Lenovo T480: throttling CPU issue

Status in linux package in Ubuntu:

Bug description:
  On Linux OS the CPU package power limit (PL1/2) is set wrong reducing
  drastically CPU performance under load.

  Apparently many Lenovo laptops (certified for Ubuntu) are affected.
  The problem is described in details here:

  There is "hacky" workaround (not compatible with SecureBoot, a Python
  script writing MSR registers periodically) :

  There is also a thread on Lenovo forum:

  I confirm the issue affect my machine running the latest kernel
  (4.15.0-45-generic, although bug affects previous releases as well)
  and using the latest firmware from Lenovo (1.19).

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: linux-image-4.15.0-45-generic 4.15.0-45.48
  ProcVersionSignature: Ubuntu 4.15.0-45.48-generic 4.15.18
  Uname: Linux 4.15.0-45-generic x86_64
  ApportVersion: 2.20.9-0ubuntu7.5
  Architecture: amd64
   /dev/snd/controlC1:  afiergol   4050 F.... pulseaudio
   /dev/snd/pcmC0D0p:   afiergol   4050 F...m pulseaudio
   /dev/snd/controlC0:  afiergol   4050 F.... pulseaudio
  CurrentDesktop: GNOME
  Date: Fri Feb  8 17:14:17 2019
  HibernationDevice: RESUME=UUID=7b4a9d17-f6d7-42ed-8f12-34f46c41cc6c
  InstallationDate: Installed on 2018-04-05 (309 days ago)
  InstallationMedia: Ubuntu 16.04.4 LTS "Xenial Xerus" - Release amd64 
  MachineType: LENOVO 20L6S04200
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-45-generic 
root=/dev/mapper/ubuntu--vg-root ro quiet splash nogpumanager 
intel_iommu=on,igfx_off iommu=pt kvm.ignore_msrs=1 vt.handoff=1
   linux-restricted-modules-4.15.0-45-generic N/A
   linux-backports-modules-4.15.0-45-generic  N/A
   linux-firmware                             1.173.3
  SourcePackage: linux
  UpgradeStatus: Upgraded to bionic on 2018-08-22 (170 days ago) 11/07/2018
  dmi.bios.vendor: LENOVO
  dmi.bios.version: N24ET44W (1.19 )
  dmi.board.asset.tag: Not Available 20L6S04200
  dmi.board.vendor: LENOVO
  dmi.board.version: Not Defined
  dmi.chassis.asset.tag: No Asset Information
  dmi.chassis.type: 10
  dmi.chassis.vendor: LENOVO
  dmi.chassis.version: None
dmi:bvnLENOVO:bvrN24ET44W(1.19):bd11/07/2018:svnLENOVO:pn20L6S04200:pvrThinkPadT480:rvnLENOVO:rn20L6S04200:rvrNotDefined:cvnLENOVO:ct10:cvrNone: ThinkPad T480 20L6S04200
  dmi.product.version: ThinkPad T480
  dmi.sys.vendor: LENOVO

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