I don't want to write a post about kde4 to explain what it is and its amazing stuff or how ugly it can be, but I think that everybody must have possibilities to install it on his computer.

I will list some methods I know using Archlinux:

• follow Churli's manual, that he derived and adapted to Archlinux from the italian famous one, but writed for ubuntu distro. This method doesn't contrast your previous KDE installation, because of it uses /opt . Here you have to compile your entire KDE 4 from official source, so to update you have to compile everything again, obviously with every update your system will have the last revision, sometimes it can be unstable. This manual is on an italian blog, so you have to translate it with your preferred method
• you can use Tanis repository, he opened some days ago thanks the realise of KDE 4.1 beta1. He offers two possibility:

  • to install KDE 4.1 beta1 in /opt with his stable repository (its enable for i686 and x86_64). You have only to add one of his two repositories, update pacman and install kde4 or kde4-all (i.e. pacman -Sy kde4-all).
  • to install KDE 4 SVN in /opt with his repository dedicated to svn realises (its enable for i686 and x86_64). You have to add one of this two repositories, update pacman and install kde4-svn or kde4-svn-all (i.e. pacman -Sy kde4-svn-all)
  • to use the scripts, used by Tanis to compile packages for his repositories.

  You can use this three methods surely not to have troubles with your previous KDE installation because of everything will be installed in /opt .

• you can use AUR PKGBUILD, you can find stable version and svn realises. You have to compile everything, I suggest to use yaourt to access to AUR from your shell (yaourt -S kdelibs4-svn, kdebase4-svn, etc ). AUR packages will be installed in /opt

There are more methods (you can search with your preferred search engine or in the official Archlinux forum) but mostly of them will create troubles with your KDE installation, because of they were created to use KDE 4 as one of yours principal DE. The most important of this category is KDEmod svn dedicated to KDE 4.

I think that to test this new DE have it installedib /opt it is the better choise, so that you can uninstall it without any problems. For this reason I suggest to create a new user to test everything freely and preserving your principal account.

Enjoy your new KDE 4 with Archlinux!

N.B. I will add links from my PC.