The entire process of upgrading Ubuntu from 6.06 LTS to 8.04.2 LTS was very smooth. After upgrade, the screen is brighter, and the sound quality is much better. Below are a few unexpected, and how I solved them.

SMP support

After the upgrade, the kernel recognizes only one CPU. Searching for "smp" in "Synaptic package manager" resulted only the older kernel for 6.06. The Ubuntu supported hardware page stated that you have to build your own kernel.

There is a  note Compiling a New Kernel that you can try to follow. But before you try that, check to see if you have the package "linux-image-generic". If you don't, install it. If you do, reboot into that kernel and see. I am able to get SMP support after I switched to the "generic" kernel.

Video program

Upgrading Ubuntu 8.04 just removed my mplayer for me. To get you mplayer back, just find mplayer in the "Synaptic package manager" and install. Install the "mplayer-nogui" if you want the CLI utility.

Follow http://help.ubuntu.com/community/RestrictedFormats if you wish to get more video support.

Firefox

Follow this post http://www.pctipsbox.com/aboutconfig-tweaks-for-firefox-3/ to tweek your Firefox for better speed and less memory usage.

Also follow this page http://googlesystem.blogspot.com/2006/04/reduce-memory-usage-in-firefox.... for some great memory reduction usage.

Install NoScript add-on. This is both for performance as well as for security. You will see a whole let less ads as well!

More security add-ons are listed in this post http://www.imminentweb.com/technologies/secure-firefox-seven-key-add-ons.

Thunderbird PGP support

Thunderbird enigmail hooks to seahorse-agent for the PGP keys. Somehow, I do get seahorse popup asking for "OpenGPG passphrase". But it doesn't accept any input.

So that's quite useless.

I've figured out a temporary work around. I installed "gnupg-agent and pinentry-qt". Then in Thunderbird, click "OpenGPG" -> "Preferences" -> "Advanced", select the checkbox "use gpg-agent for passphrases". Then run "gpg-agent --daemon". This will create a directory in /tmp, something like /tmp/gpg-kg0PTo/.

Now restart your Thunderbird, click on a message that's PGP-ed. It will complain. Check the error message, which tells you it is trying to find the S.gpg-agent in a non-existing directory. Create a soft link to the gpg-agent folder we got ealier (like /tmp/gpg-kg0PTo/), so that the non-existing directory now point to the gpg-agent folder.

That should solve the problem for now.

Power management

After upgrading to ubuntu 8.04, hibernation means shuting down the computer forcefully, and suspension would only wake up with a blank screen for me to stare at. I am using ACPI. So this is not very useful.

With some experience, I am able to do the following:

In Power manager, set "put computer to sleep after x min inactive", and set "blank screen when laptop lid is closed".

Temperature

Install "computertemp" and "hddtemp" to monitor the temperature of your CPM and hard drive.

Game package

Unlike previous version, Ubuntu 8.04 now allow you to remove the game package entirely.

Performance turning

• Tune Gnome desktop: This article "Gnome Improving Performance"should still be valid for speeding up gnome desktop.
• Open your session manager, and disable any programs that you don't need be run all the time. This will prevent these program be started whenever you login to your session.
• How to tune your Ubuntu PC for faster performance
• Hacking Ubuntu to Improve Performance