Tag Archives: Desktop environment

How to install Ubuntu 12.04 on old computers with non PAE CPU

When I tried to install Ubuntu 12.04 on an old ThinkPad X40 I was surprised to discover this warning on my screen:

This kernel requires the following features not present on the CPU:
pae. Unable to boot - please use a kernel appropriate for your CPU.

In few words I wasn’t able to install Ubuntu 12.04 because the kernel on Ubuntu 12.04 was not supporting my CPU and I was really upset because I have always promoted Linux distributions as the most versatile and appropriate OS to keep using “old” hardware.

Sincerely, as described in an older post, I previously decided to install MATE desktop environment because the graphic cards on many laptops didn’t support Unity and Gnome 3 but this was the first time I had to renounce the installation of Ubuntu. I didn’t want to surrender to this difficulty (that appeared to me as a bug)!

First of all, I discovered that pae is “a feature to allow 32-bit x86 processors to access a physical address space (including random access memory and memory mapped devices) larger than 4 gigabytes“. After I clarified this point, I was not sure that my processor was totally inadequate to support Ubuntu 12.04.

After some web surfing I discovery that there are two easy solutions to avoid this problem.

1 – As first solution you can install Lubuntu (my choice) or Xubuntu on your computer then you can install the ubuntu-desktop using the Package Manager.

2 – If you prefer not to use the Package Manager you can install Ubuntu 11.04 or 11.10 and then upgrade Ubuntu to 12.04.

More in general, it is also possible to assume that if you have a non PAE CPU, your hardware could not be able to support the Unity desktop. For this reason you can keep your Lubuntu – Xubuntu (based on the light but effective LXDE desktop) or switch your desktop environment to Gnome (the Classic, of course) installing the gnome package instead of ubuntu-desktop.

In any case, if you want to know if your CPU supports pae you have to open a Terminal and type:

grep --color=always -i PAE /proc/cpuinfo

If something like “flags: fpu vme de pse tsc msr pae mce cx8…” outputs on your Terminal, you have a pae CPU otherwise your CPU doesn’t support pae.

The good third choice: MATE desktop environment. The traditional but rock solid solution for the Unity unhappy users (when also Gnome fails)…

2 Replies

My first Linux OS was a Knoppix but I had so many problems with the hardware drivers, the LAN configuration and the monitor settings that I was really discouraged. After many tests I decided that Ubuntu was the right OS for my notebooks and I continued to use it without any particularly matters till Unity.

Unity is nice to see, intuitive but if you use your OS in a stressful way (I mean doing three or four different tasks all together: reading emails, talking with Skype and writing on LibreOffice), you spend too much time looking for the icon you need to launch the right program. The vertical monitor space has not enough room to visually show all the icons related to programs I use everyday. Surely this is my personal matter but I actually prefer the “old” graphic interface. For this reason I decided to install Gnome 3 but my vetust IBM Thinkpad crashed a couple of time in a week.

To my surprise also the Gnome Classic option encountered some crashes due to the amount and diversity of the software I installed on my laptop during the last years.

As usual, after some web searches I found a solution: MATE. This particular desktop environment is a fork of Gnome 2 and it really looks very intuitive and easy to use. If some software conflicts with the MATE environment, a pop-up message will appear on your sceeen and, if you have the patience to read the Details contained in it, you will able to solve your problems. In my particular case (don’t ask me why) it helped me to focus my attention on Conduit which caused the crashes on Gnome.

To easily install MATE, on almost every Linux distribution, you can read its wiki dedicated page or directly follow the below instruction if you use Ubuntu 12.04.

– open Terminal and type these command lines:

sudo add-apt-repository "deb http://repo.mate-desktop.org/ubuntu oneiric main"

sudo apt-get update

sudo apt-getinstall mate-archive-keyring

sudo apt-get update

sudo apt-get install mate-core

sudo apt-get install mate-desktop-environment

When the Terminal finishes all the upgrade stuff, reboot your Ubuntu 12.04 and select MATE on the login screen (click on the upper right “gear” and choose MATE).

That’s all! Have a good week!