exactly what happened to me, kept reinstalling 20.04.2 then decided to update apps in batches leaving thermald to last as it seemed must likely candidate. then i discovered Timeshift (old image restorer) save a lot of time! On 06/06/2021 01:20, Junjie Jin wrote: > I encountered the similar issue since 1.9.1-1ubuntu0.4 update. On the > previous version 1.9.1-1build1, if I run a CPU stress test, the fan will > keep going up until full speed (~6000rpm) as the temp rises. On > 1.9.1-1ubuntu0.4, the fan sometimes is kept at 3600rpm or remains at > zero. Once CPU reaches over ~90C, it got throttled down to min freq > 400MHz. I didn't know the problem was thermald until I reinstalled a > fresh Ubuntu 20.04.2, which worked perfectly, and then basically did a > binary search to find which package update caused the issue. To verify > it's really thermald 1.9.1-1ubuntu0.4, I reinstalled Ubuntu 20.04.2 > again, and the fan worked fine as expected, and then updated thermald > alone, and this issue happened. Then I downgraded thermald to the stock > version come with Ubuntu 20.04.2, the issue went away. > > lshw --short: > system Latitude 7400 (08E1) > /0 bus 07WDVW > /0/0 memory 64KiB BIOS > /0/20 memory 32GiB System Memory > /0/20/0 memory 16GiB SODIMM DDR4 Synchronous 2667 MHz (0.4 ns) > /0/20/1 memory 16GiB SODIMM DDR4 Synchronous 2667 MHz (0.4 ns) > /0/29 memory 256KiB L1 cache > /0/2a memory 1MiB L2 cache > /0/2b memory 8MiB L3 cache > /0/2c processor Intel(R) Core(TM) i7-8665U CPU @ 1.90GHz > /0/100 bridge Coffee Lake HOST and DRAM Controller > /0/100/2 display UHD Graphics 620 (Whiskey Lake) > /0/100/4 generic Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem > /0/100/8 generic Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th/8th Gen Core Processor Gaussian Mixture Model > /0/100/12 generic Cannon Point-LP Thermal Controller > /0/100/14 bus Cannon Point-LP USB 3.1 xHCI Controller > /0/100/14/0 usb1 bus xHCI Host Controller > /0/100/14/0/6 multimedia Integrated_Webcam_HD > /0/100/14/0/8 generic 58200 > /0/100/14/0/a communication Bluetooth wireless interface > /0/100/14/1 usb2 bus xHCI Host Controller > /0/100/14.2 memory RAM memory > /0/100/14.3 wlo1 network Cannon Point-LP CNVi [Wireless-AC] > /0/100/15 bus Cannon Point-LP Serial IO I2C Controller #0 > /0/100/15.1 bus Cannon Point-LP Serial IO I2C Controller #1 > /0/100/15.3 bus Intel Corporation > /0/100/16 communication Cannon Point-LP MEI Controller #1 > /0/100/16.3 communication Cannon Point-LP Keyboard and Text (KT) Redirection > /0/100/19 bus Cannon Point-LP Serial IO I2C Host Controller > /0/100/1c bridge Cannon Point-LP PCI Express Root Port #5 > /0/100/1c/0 bridge JHL6340 Thunderbolt 3 Bridge (C step) [Alpine Ridge 2C 2016] > /0/100/1c/0/0 bridge JHL6340 Thunderbolt 3 Bridge (C step) [Alpine Ridge 2C 2016] > /0/100/1c/0/0/0 generic JHL6340 Thunderbolt 3 NHI (C step) [Alpine Ridge 2C 2016] > /0/100/1c/0/1 bridge JHL6340 Thunderbolt 3 Bridge (C step) [Alpine Ridge 2C 2016] > /0/100/1c/0/2 bridge JHL6340 Thunderbolt 3 Bridge (C step) [Alpine Ridge 2C 2016] > /0/100/1c/0/2/0 bus JHL6340 Thunderbolt 3 USB 3.1 Controller (C step) [Alpine Ridge 2C 2016] > /0/100/1c/0/2/0/0 usb3 bus xHCI Host Controller > /0/100/1c/0/2/0/1 usb4 bus xHCI Host Controller > /0/100/1d bridge Intel Corporation > /0/100/1d/0 generic RTS525A PCI Express Card Reader > /0/100/1d.4 bridge Cannon Point-LP PCI Express Root Port #13 > /0/100/1d.4/0 storage SK hynix > /0/100/1d.4/0/0 /dev/nvme0 storage PC601 NVMe SK hynix 512GB > /0/100/1d.4/0/0/1 /dev/nvme0n1 disk 512GB NVMe namespace > /0/100/1d.4/0/0/1/1 volume 511MiB Windows FAT volume > /0/100/1d.4/0/0/1/2 /dev/nvme0n1p2 volume 732MiB EXT4 volume > /0/100/1d.4/0/0/1/3 /dev/nvme0n1p3 volume 475GiB EFI partition > /0/100/1f bridge Cannon Point-LP LPC Controller > /0/100/1f.3 multimedia Cannon Point-LP High Definition Audio Controller > /0/100/1f.4 bus Cannon Point-LP SMBus Controller > /0/100/1f.5 bus Cannon Point-LP SPI Controller > /0/1 system PnP device PNP0c02 > /0/2 system PnP device PNP0c02 > /0/3 system PnP device PNP0b00 > /0/4 generic PnP device INT3f0d > /0/5 input PnP device PNP0303 > /0/6 generic PnP device DLL08e1 > /0/7 system PnP device PNP0c02 > /0/8 system PnP device PNP0c02 > /0/9 system PnP device PNP0c02 > /0/a system PnP device PNP0c02 > /1 power DELL K4Y2J9B >