Interesting claims you've made, but since the system has Dell support for Ubuntu 20.04 LTS, they're just one opinion -- not fact.

Please install Ubuntu 20.04 LTS.  Run the unigine valley or heaven benchmark:

https://benchmark.unigine.com/

Install turbostat:

  $ sudo apt install linux-cpupower

Run turbostat when the benchmark is running.  Check the GFXAMHz metric after a minute.  If you are getting more than 900MHz, I'll eat my words.  I bet you get 100MHz and 3fps.

Reproducible bugs are not opinions.

Any comments from Dell representative? I was planning buy one and install Debian but this sounds like a no go.

I took the bait and bought 5420 with cheapest Core i5 configuration. I downloaded Ubuntu 21.04 ISO and booted into live mode. Then I downloaded FurMark for Linux https://www.geeks3d.com/20140304/gputest-0-7-0-opengl-benchmark-win-linux-osx-new-fp64-opengl-4-test-and-online-gpu-database/

I run FurMark in windowed mode and checked turbostat. It reported GFXAMHz 1300 during the test and 100 when idle.

I can confirm there is no problem with GPU power management, at least in latest Ubuntu.

I install ubuntu 21.10 normal but WI-FI Driver does not work

hello my pc Latitude E5470 supports or not supported

I have exactly the same machine (dell latitude 5420, 2TB SSD, 32G RAM, i7) and I have been noticing some problems with CPU at 100% with no apparent reason now and then on ubuntu 20.04. I also use a windows environment as a guest in a virtualbox for developing applications and the performance is worse than it used to be on a dell latitude 5400.

I run valley test as you said and noticed that sometimes it runs okay and I can see GFXAMHz going all the way to 1300MHz but at some the test start failing, rendering is not good anymore and I can see GFXAMHz  in 100MHz so I guess Im hiting the same problem here

Did you manage to fix this problem? Is there any solution from dell? it is possible to update the BIOS to fix this problem? I understand this machine has support for ubuntu 20.04

Found a solution. I updated the bios of my laptop to the last version (december 2021) and everything works like a charm now. I run ubuntu 20.04.

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@Linux Engineer wrote:

I got this system as a Linux development platform.  Several of my colleagues have used XPS systems in the past.  I bought a top-spec'd system (2TB SSD, 32G RAM, i7) mostly because the Tigerlake cpu had higher TDP than the parts used in competing laptops.

Unfortunately, the BIOS for this system completely disables power management on Linux.  Even though it has a large TDP envelope, the GPU will max out at 100MHz (instead of 1.35GHz) due to the closed power-management firmware.  This make the device useless on Linux.

A developer from the thermald project reverse-engineered the laptop, and got the GPU clock up to 400MHz, which improves the situation but still it is slower than laptops from 5 years ago.

If Dell is going to choose BIOS solutions that make platforms unusable on Linux, they should make it clear on the website:  "This device will never run Linux".  Until then, perhaps shoppers will find this post and choose another platform for their Linux needs. rapidfs

The other option is for Dell to take 5 minutes and publicly document the power management scheme so Linux projects can optimize power control for this platform.

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Looking for the same issue. Bumped into your thread. Thanks for creating it. Looking forward for solution.