I used konstruct to download kde 3.5.1, no problems there.. got all the files installed into /root/kde3.5.1 and under my user home /home/keith/kde3.5.1 and i was wondering what i must do next in order to startup under kde 3.5.1 instead of the old 3.4 installed on my mandriva 2006.. Any info would be much appreciated! Thanks!

If you have installed it wouldnt it write over the old version? You could have a look at uninstall options and see if both versions come up. I doubt it but I guess it depends on how you installed it.

Try typing kde at a console prompt (cli)
I tried and it just tells me the server is running
Dont know how to get the version
What is konstruct anyway?

Konstruct is an automated tool that can build an entire KDE stable or development build of KDE from source. Konstruct does not overwrite the old KDE release unless you specifically edit the config files to let it install into the same prefix. I sometimes run two versions of KDE, one stable and one development. I use the tips in this article to setup the development versions environment, once I have finished compiling from source. You can also make an entry in KDM for the new version, just use the old KDE entry in /usr/share/apps/kdm/sessions as a guide.