Thursday, July 12, 2012

ASUS Zenbook UX31E and Kubuntu 12.04: some tips

After a couple of months with this ultrabook as my main computer at work, I wanted to share a few tips. First of all, I am using Kubuntu 12.04, so I followed the instructions in Community Ubuntu regarding this computer. These are very useful and I advice anyone to follow them, except for one thing that I will comment on later.

There are lots of reviews of this computer out there, so I will be very shallow here:
  • It is fast and responsive. The SSD hard disk plus the intel iCore 5 and the 4GB of RAM make this a fast computer (though obviously not for hard gamers, graphic designers, movie makers etc.).
  • It is light, thin and beautiful. People are usually impressed by its looks.
  • The screen is good, but improvable: fantastic resolution, good brightness/contrast, decent colors, not very good viewing angles and glossy (I prefer matte screens). Again more than enough for many users, but not for all.
  • The clickpad is not as bad as I expected after reading some reviews. For Ubuntu users there is more information in the link I have included before. I do not use it in a daily basis (I prefer a wireless mouse), but for an occasional use I find it more than acceptable.
  • The keyboard is bad. It has flat and separated keys with a few minor issues (the key action is short, the feeling is not very good) and a big one: some key presses are not detected. In some keys, if you press them on a side the key press is not detected, so you make a typo. After a couple of weeks using it, I decided that it was enough and I bought a wireless keyboard. For occasional use it is not that bad, but it is not good for writing long texts in a daily basis.
  • I do not use it unplugged for long periods, so I cannot tell much about the battery life (the tray icon in Kubuntu gives between 6 and 7 hours, but I do not know if that is true).
Now a few tips that I have learned over these weeks of using this laptop with Kubuntu 12.04 (there are many other useful tips in the instructions in Community Ubuntu):
  • The USB Ethernet adapter must be plugged in the left USB port (USB 2.0), not in the rigth one (USB 3.0). It works in both of them, but in the USB 3.0 port the network is far slower.
  • If you are having random system freezes (you can move the mouse cursor but nothing else is responding; some times you can change to a virtual terminal (i.e. Ctrl-Alt-F1) and do something, and others you just have to make a hard reset) check your kernel logs for "GPU hungs". In a terminal, write: "cat /var/log/kern.log | grep GPU". In KDE you can also use the graphical tool KSystemLog. If you see something like "[drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung ... [11959.817883] [drm:kick_ring] *ERROR* Kicking stuck semaphore on render ring" when you suffered the freezes, then I suggest you to make sure that in your kernel parameters you have "i915.semaphores=0" (the instructions in Community Ubuntu suggest to give this parameter a 1; follow those instructions but put a 0 instead (*)). I suppose this can be helpful too for other computers with Sandy Bridge and an Intel HD 3000 graphics card running an Ubuntu-based Linux distro and having this problem. This has completely fixed this problem for me.
  • I run the synaptiks application on the system start, and I have configured it to have the clickpad automatically disabled when I am typing on the keyboard or when an external mouse is connected. This is a very important usability improvement if you are using the laptop keyboard.
  • I have detected screen tearing in videos (this is the worst problem I always have with Linux; in my home laptop I have not been able to solve it after trying everything). I haven't worked too much on this issue, I do not use this computer for watching movies but, for now, I strongly recommend VLC over the default Dragon Player in Kubuntu. With the out-of-the-box configuration, the VLC version included in the Ubuntu repositories shows no tearing at all in movies where Dragon Player shows a lot of it. This may work for you or not, as tearing depends on many things, but for now it is an acceptable and simple workaround for me.
If I can think of something else, I will update this post, unless it is something long enough that deserves a new one.



(*) And do not forget to run "sudo update-grub" after changing /etc/default/grub, some people are known for having committed this mistake before... ;-)