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[Bug 1535426] Re: CPU runs at high speed after upgrade

 

Tried switching to 3.19 kernel - still high speed.
Tried switching to intel X driver instead of modesetting: CPU still runs at high speed.

The only changes I haven't backed out are:
a) The Ubuntu 15.10 userland.
b) The BIOS update from 1.07 to 1.10.

With absolutely quiescent system, under modesetting driver, CPU will
settle at 800MHz, but wiggling the mouse or outputting to an xterm
causes the CPU speed to rise. Under intel driver, an apparently
absolutely quiescent system seems to use more CPU than under
modesetting.

powertop is reporting power usage between 12 and 26 W, whereas
previously with 15.04 I had power usage of 5-8W.

Please help, this is killing me. No battery = no computer.

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https://bugs.launchpad.net/bugs/1535426

Title:
  CPU runs at high speed after upgrade

Status in linux package in Ubuntu:
  Confirmed

Bug description:
  After a dist-upgrade from 15.04 to 15.10, moving from kernel 3.19.0-43
  to 4.2.0-23, my laptop CPU runs continuously at 3GHz, and never slows
  down to 800MHz, as it used to. This has reduced my battery life from
  24 hours to 8 hours.

  ProblemType: Bug
  DistroRelease: Ubuntu 15.10
  Package: linux-image-4.2.0-23-generic 4.2.0-23.28
  ProcVersionSignature: Ubuntu 4.2.0-23.28-generic 4.2.6
  Uname: Linux 4.2.0-23-generic x86_64
  ApportVersion: 2.19.1-0ubuntu5
  Architecture: amd64
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC1:  shevek     2664 F.... pulseaudio
   /dev/snd/controlC0:  shevek     2664 F.... pulseaudio
  CurrentDesktop: XFCE
  Date: Mon Jan 18 11:38:29 2016
  HibernationDevice: RESUME=UUID=22fd2208-7557-432d-bbff-95dd97905323
  InstallationDate: Installed on 2015-05-18 (244 days ago)
  InstallationMedia: Xubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422.1)
  MachineType: LENOVO 20CKCT01WW
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.2.0-23-generic.efi.signed root=/dev/mapper/xubuntu--vg-root ro noprompt persistent quiet splash vt.handoff=7
  RelatedPackageVersions:
   linux-restricted-modules-4.2.0-23-generic N/A
   linux-backports-modules-4.2.0-23-generic  N/A
   linux-firmware                            1.149.3
  SourcePackage: linux
  UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
  UpgradeStatus: Upgraded to wily on 2016-01-17 (1 days ago)
  dmi.bios.date: 08/20/2015
  dmi.bios.vendor: LENOVO
  dmi.bios.version: N11ET34W (1.10 )
  dmi.board.asset.tag: Not Available
  dmi.board.name: 20CKCT01WW
  dmi.board.vendor: LENOVO
  dmi.board.version: 0B98417 WIN
  dmi.chassis.asset.tag: No Asset Information
  dmi.chassis.type: 10
  dmi.chassis.vendor: LENOVO
  dmi.chassis.version: None
  dmi.modalias: dmi:bvnLENOVO:bvrN11ET34W(1.10):bd08/20/2015:svnLENOVO:pn20CKCT01WW:pvrThinkPadT550:rvnLENOVO:rn20CKCT01WW:rvr0B98417WIN:cvnLENOVO:ct10:cvrNone:
  dmi.product.name: 20CKCT01WW
  dmi.product.version: ThinkPad T550
  dmi.sys.vendor: LENOVO

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