Comment 0 for bug 1838141

intel_pstate not working. CPU frequency fixed at 800MHz.

I've tried to modify frequency using "cpufreq-set" and also by directly writing to files in "/sys/devices/system/cpu/cpu0/cpufreq/*" to no success.

I tried different versions of kernel, it started working on 4.17.0 but stopped working soon. These are the versions I tested.

5.2.3 - Not Working
5.1.0 - Not Working
4.19.60 - Not Working
4.18.20 - Not Working
4.17.19 - Not Working
4.17.10 - Not Working
4.17.5 - Not Working
4.17.3 - Working
4.17.2 - Working
4.17.1 - Working
4.17.0 - Working
4.16.18 - Not Working
4.15.0 - Not Working

Please let me know if anything else is needed.
thanks

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-4.15.0-55-generic 4.15.0-55.60
ProcVersionSignature: Ubuntu 4.15.0-55.60-generic 4.15.18
Uname: Linux 4.15.0-55-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: srijan 2219 F.... pulseaudio
CurrentDesktop: KDE
Date: Sat Jul 27 11:34:10 2019
InstallationDate: Installed on 2018-11-25 (243 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 003: ID 0bda:5621 Realtek Semiconductor Corp.
 Bus 001 Device 002: ID 046d:c534 Logitech, Inc. Unifying Receiver
 Bus 001 Device 004: ID 8087:0aaa Intel Corp.
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Acer Predator PH315-51
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-55-generic root=UUID=a76bd009-8058-4e96-a8b5-a82b7fbe1ede ro acpi_backlight=vendor i915.modeset=1 i915.enable_guc=3 i915.enable_dc=2 i915.enable_fbc=1 nvme_core.default_ps_max_latency_us=18000000 pcie_aspm=force i915.enable_psr=2 i915.disable_power_well=1 nmi_watchdog=0
RelatedPackageVersions:
 linux-restricted-modules-4.15.0-55-generic N/A
 linux-backports-modules-4.15.0-55-generic N/A
 linux-firmware 1.173.10
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
WifiSyslog:

dmi.bios.date: 12/05/2018
dmi.bios.vendor: Insyde Corp.
dmi.bios.version: V1.24
dmi.board.asset.tag: Type2 - Board Serial Number
dmi.board.name: Sienta_CFS
dmi.board.vendor: CFL
dmi.board.version: V1.24
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: V1.24
dmi.modalias: dmi:bvnInsydeCorp.:bvrV1.24:bd12/05/2018:svnAcer:pnPredatorPH315-51:pvrV1.24:rvnCFL:rnSienta_CFS:rvrV1.24:cvnAcer:ct10:cvrV1.24:
dmi.product.family: Predator Helios 300
dmi.product.name: Predator PH315-51
dmi.product.version: V1.24
dmi.sys.vendor: Acer