Lenovo x200s high pitch whine (When AC is plugged in using dock)

will.price94 · 2013-07-22 17:36:50

Hi,

I've got a lenovo x200s notebook which emits a high pitched irregular noise from around the CPU area of the motherboard. I dock it using a x200 ultrabase dock which is hooked up to my external monitors. It's got a Core2Duo L9400, which I believe to be the cause of the issue.

Conditions under which the high pitch noise is emitted:

AC plugged in
Docked (with AC adapter attached to the dock, or to the laptop itself)
CPU isn't utilized

Causes ruled out

It's definitely not the inverter as that makes another high pitched noise, but only when the brightness isn't on full. Disabling the internal screen makes no difference to the non-inverter related noise.

I'm almost certain the noise is not coming from the dock, and is coming from around the CPU area as it can be heard most prominently next to the fan. And no, It's not the fan.

What I've tried to remedy it

Whenever I utilize the CPU, such as compiling programs, the high pitch noise cuts out completely. When I scroll in firefox it also cuts out (CPU utilization again I presume).

# cpupower frequency-info

analyzing CPU 0:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 10.0 us.
  hardware limits: 800 MHz - 1.87 GHz
  available frequency steps: 1.87 GHz, 1.87 GHz, 1.60 GHz, 800 MHz
  available cpufreq governors: conservative, powersave, userspace, ondemand, performance
  current policy: frequency should be within 1.87 GHz and 1.87 GHz.
                  The governor "performance" may decide which speed to use
                  within this range.
  current CPU frequency is 1.87 GHz (asserted by call to hardware).
  cpufreq stats: 1.87 GHz:100.00%, 1.87 GHz:0.00%, 1.60 GHz:0.00%, 800 MHz:0.00%
  boost state support:
    Supported: yes
    Active: yes

(I've been setting both cores using a `for` loop)

`performance` is loaded whenever I do anything intensive like use `burnMMX`, or compile etc, I don't know how to turn this behaviour off. If I set it to some other governor it just jumps back to `performance` when doing those tasks. The noise is better at 800MHz , and I find that `conservative` is the least noisy by a small margin; this is probably due to the way it switches[1] more gracefully than `ondemand`, or that it runs at 0.8GHz most of the time.

With `performance` and `ondemand` the beep is high pitched and irregularly on and off, again, probably due to running at a higher clock frequency than with `conservative`. With `conservative` the beep is more regular on off , it sounds the same as when set fixed at 0.8GHz on the `userspace` governor.

With any governor, when doing something CPU intensive the sound abates.

It's silent when:

On the dock without the AC adapter
Off the dock with and without the AC adapter

Any ideas would be MOST gratefully appreciated. It's very bothersome to me, and I think I'll sell the laptop if I can't remedy it.
[1] https://www.kernel.org/doc/Documentatio … ernors.txt

mkllnk · 2014-01-22 01:48:11

Hi,

I have the same problem but without the dock. Just when the AC adapter is plugged in I can hear this high pitch whine. I tried all different power setting in the BIOS and found out that Config -> Power -> CPU Power Management has an impact. Changing the value from automatic to disabled avoids the sound. But for me saving power is more important than this noise. My noise is quite subtle but when you are aware of it then it can make you crazy. ;-)
Then I found another hint that 'rmmod uhci_hcd' can reduce the sound and it does on my X200s. It seems that there are two noises and one of them is connected to the USB. This sound also disappears when I plug in my USB mouse. So if you are using a mouse, fine. If not, you can safely remove the module. USB memory sticks still work.

I got this hint from a cool summarizing page for this issue:
http://www.thinkwiki.org/wiki/Problem_w … tch_noises

The remaining even lower noise seems not be connected to the CPU because running the command yes, which keeps the CPU working, eleminates only the noise wich goes by deactivating USB or plugging in the mouse.

ewaller · 2014-01-22 02:17:48

Does your system have any microphones? Were I you, I would fire up your mixer and turn off all of the audio inputs (line-in, microphone, etc...) I have seen systems where microphonics generated by the power supply, disk drives and EMI generated by back light inverters couple into the microphones and are then amplified by the audio amplifiers and come out through the speakers. It may not be your problem, but it is worth a look.

Arch Linux

#1 2013-07-22 17:36:50