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XPS 9350 cpu limited to 400MHz in Linux only
For the last month or so, the CPU in my XPS 13 9350 is stuck at 400MHz. I dual boot Windows 10 and Arch Linux. The problem is only present with Linux. Windows 10 works fine. I've see a similar problem where XPS 15 is limited to 800MHz. However, this is a different bug since the fix there of disconnecting the battery doesn't work, and that issue persists across OS's. Whereas mine only happens on Linux. I've tried using cpupower to change the min frequency and the power governor to no effect. I've also tried disabling the intel_pstate driver and that also has no effect. What can this issue be? I can't find anything on Google about anyone having a similar issue(specifically where the CPU is stuck at 400MHz). I've posted on the Arch Linux forums which is visible here(
https://bbs.archlinux.org/viewtopic.php?pid=1906231) and I describe one other fix I tried where I used msr-tools to try and reset a register. This also didn't work. Does anyone have any ideas on how to debug this issue further?
landtuna3
1 Message
0
May 21st, 2021 07:00
Well, it's been a year since you posted, but I have this problem, too, on a Latitude 7400 and Ubuntu 20.04. Did you have any luck getting it to work? I saw posts about older Dell laptops having a stuck CPU until people removed a screw under the C key on the keyboard! Apparently hundreds of people have fixed it that way.
blob007
81 Posts
0
May 21st, 2021 15:00
I randomly got this at one point as well (XPS 9300 2020, kernel 5.11). After a long time without shut downs, with multiple dock and power adapter reconnects/disconnects, my CPU got stuck @ 400MHz. It would not reset after reboot and needed a full shutdown to return to normal. I wasn't able to reproduce this issue afterwards...
Boeroboy
1 Message
0
December 19th, 2023 00:46
Hi I see this is old but I've been chasing it for a 9310 I adopted too. This is an annoying feature called Intel MSR and if you write to a special register it can force the CPU to release it's throttle locking. This is not a permanent setting and must be reset each boot. Also Secure Boot must be disabled for write access which is kind of crazy. Windows has the same mechanism.
The thread that helped me:
https://superuser.com/questions/1160735/stop-dell-from-throttling-cpu-with-power-adapter