Laptop freezing when AC is plugged and chargi

[meneldor]

Hello,

I bought a new laptop Dell Latitude E5420 i5/8GB/128GB SSD.
The first OS ive installed is Kubuntu Precise. I am surprised how all is working after the install (except some buttons). I had some problems booting from the SSD but resoved it installing lastest grub2 packages using the Recovery console.

The first problem appeared. When I plugged the AC adapter to the laptop the system became extremely slow. When I move the mouse it barely moves. I noticed that one of the kworker processes is growing in CPU usage very fast.
Once the battery is full or i unplug the cable everything becomes stable again so this happens only when the battery is charging. I cannot find anything in the log files and i am not sure but it might be since the last update. I will check what ive updated.

Regards

[meneldor]

Could anyone point me to any direction please? This issue is really annoying and i cannot touch the laptop when the battery is charging.

[vw72]

Seems to be a common problem (not just Ubuntu). Check the end of this thread for a fix: http://ubuntuforums.org/showthread.php?t=1885546

[meneldor]

Thank you, vw72! The solution seems to be if i add options drm_kms_helper poll=N to /etc/modprobe.d/local.conf

[GreyGeek]

If that fix solved your problem don't forget to mark your first post "SOLVED"! Thanks!

[meneldor]

Yes, this solved my problem. Thanks!