Installing Ubuntu Oneiric Ocelot on a new Dell Latitude E5420

My old Dell Precision died a few weeks ago. The graphics card seemed to die suddenly and without warning: the monitor screen is now merely backlit black; and plugging a second monitor on yields the sort of blinking gibberish you used to get when you reset a ZX Spectrum.

Despite their mediocre environmental record, Dell were my choice of replacement as they're one of the best of a bad bunch. They're rather cagey about Ubuntu support - and no longer sell preinstalls in the UK from what I can see - but we had recently bought a Latitude E5420 for the office and successfully installed Ubuntu Oneiric on it, I think. So this was a known quantity: even though it was tempting to buy a Macbook Pro and install Ubuntu on it, the installation guide was sufficiently problematic at the time of purchase for it to put me off (especially the possible temperature sensor problems.) I just wanted something that would work.

After my Latitude E5420 was delivered, I began an installation of Ubuntu Oneiric Ocelot on it. This was initially hampered by a badly burned Live CDROM: honestly, why are we still using these dreadful plastic things these days? Yet while you can jump through hoops to build "Live USB sticks", the default remains yet another Ubuntu bird-scarer. Eventually, though, it was installed and running fine:


  • GOOD: Wifi and Bluetooth both work out of the box.
  • GOOD: Sound and video are great, including second monitor support.
  • OK: Power management isn't brilliant, but powertop really helped configure the system.
  • POOR: The built-in webcam keeps resetting to pitch-black defaults, especially when used with Skype. Not clear why.
  • BAD: With an encrypted home directory, the machine will not recover properly froom hibernation.


My initial impression of the much-maligned Unity was that it was simply a different way of doing things from Gnome: more like OSX plus Quicksilver than Gnome's kind-of souped-up WinXP. However, as I tried to use it further, I kept coming up against quite nasty software failures. The CompizConfig Settings Manager (you're meant to know what ccsm stands for, by the way) frequently crashes when I turn certain plugins on and off; and Unity's about:config causes my entire display to hang under a still-moveable mouse, which ironically happened while I was writing this blogpost.

For some time Unity also flatly refused to start properly (launcher and menu bar would never appear) and I had to make do with Unity 2D. Eventually, with no intervention on my part, it just started working again. Who knows what was going on? And what fixed it? There are a few things I have been able to fix, though, with varying levels of success:

  • The launcher icons, too big on a 14" display, can be resized with ccsm using experimental features. This setting is unfortunately ignored when you fall back to Unity 2D.
  • Third-mouse-button emulation doesn't work out of the box, but it's quick to fix with a legacy Gnome program. However, the fix doesn't always appear to manifest itself in Unity itself. So not much of a success story, then.
  • After using a second monitor, my display suddenly behaved very odd indeed: there was a two or three second delay between moving my mouse or pressing a key, and having it appear on the screen. At the same time, my system would run "hot", with kworker processes taking up at least a couple of CPU threads almost full time. A lot of hunting around  led to me adding the following line in /etc/modprobe.d/local.conf:

options drm_kms_helper poll=N

In fact, if you google for that kernel module (drm_kms_helper) you essentially get a long list of people complaining about its effect on system load, plus a rather swamped explanatory page that it's something to do with being able to set display parameters in kernel space rather than user space.

Generally speaking, I'm happy with my machine and broadly happy with Unity: I think some of the criticisms of it are misplaced. Certainly in the whole of this long rant by esr, there's only one objectively valid point, that binary config files have no place in a Linux distribution. The rest can just be considered a write up of a single round of user-testing: informative as far as it goes, but in no way definitive.

I would say, though, that I don't "trust my weight" to this machine the way I've done with previous ones. Unity is still not what one would call full-release code: while not alpha, it's certainly not much beyond beta; about:config should never crash your display, ever, and other glitches make it possible to entirely lose your work, unless you're in a Google doc or at the command line.

While I'm not yet planning to jump ship to Linux Mint, I'm certainly hoping that April 2012's Precise Pangolin, as an LTS release, will fix a number of these quite serious stability issues. Graphical stability over graphical fanciness every day; and with that in mind I'd advise anyone who wants their machine to be ridiculously stable, yet still with a Debian-based and graphically pleasant OS, to stick with the previous LTS, Lucid Lynx.


The fix to third-button emulation can be made permanent by typing the following at a command line:

gsettings set org.gnome.settings-daemon.peripherals.mouse middle-button-enabled true

Why the GUI doesn't do this when it apparently fixes it for the current session is beyond me.