Hi,
Sorry to have asked a newbie question. If the information already exists, please point me to that.
I have installed Tumbleweed with KDE. It is a bit heavy for my old hardware. I am new to Linux.
Can I install xfce over it? Please give the steps.
Do I need to re-install all the software, if I switch?
Can I have multiple-DEs in the setup and switch as required? Are the configurations / installed software are saved when we switch?
1 You don’t install over a desktop you can install many desktops. In Yast Software Management select patterns and select the pattern for the Desktop you want to add.
You can choose which desktop from the login screen
2 No
3 see 1 above
and welcome
Yes. Just select the Patterns view in Yast Software Management, and then select “XFCE Desktop Environment”
I’ve been doing that for years. But I didn’t do it for Leap 15.2, because I rarely login to XFCE.
On the login screen, you can select which desktop environment to use. The different desktops mostly save settings in different places, so they don’t interfere with one another.
For most Users,
Once you install the Destkop (pattern as described) and simply logout, select your new Desktop and log back in.
A detail which may not matter to most is that you will use the same Window Manager and Desktop Manager as your originally installed Desktop.
If you want the full experience as intended by the Maintainers of your Desktop, you’ll need to manually switch over your DM and WM as well using Alternatives… either by command line or the YaST Alternatives module.
TSU
Not correct. I think you meant display mangers here. A new DE will have it’s own window manager.
Worked fantastic. I have installed xfce. All applications available. No need to reinstall. The difference in RAM usage in only when there is a high demand for it, like too many tabs in the browser. xfce keeps the usage to minimum(don’t grow much), whereas in KDE it keeps growing.
Tumbleweed is the best OS for beginners. Everything works smoothly from the beginning. No need to get under the hood to fix up thing, which becomes a bottleneck for a new user.
Thanks for your prompt responses. This is a very supportive forum. I will stick to Tumbleweed for a long a time now. I marked the thread as solved in the subject line.
TW is a rolling release (bleeding edge) thus sometimes has problems a newbee may have serious problems with. Leap is more stable and seldom has update problems.
I consider myself a permanent beginner, but run 1-2 hands full of TW installs for some years now (besides some Leap installs). On important machines I don’t run TW updates (usually once a week) before trying on less important machines. Most update problems were annoying in the past but not really killing off the install (OK, some years ago the networking went dark iirc…).
So: be carefull and don’t update (especially around shifting to new kernel releases) without having a look in the forums and if you don’t have time to resolve some (minor) issues. 
Cool. Thanks for sketching up the idea of updates. The level of danger seems minimal. I have seen W giving BSOD after updates. It happened so many times. There is much less vulnerability in TW. That much risk I can take to stay on the bleeding edge.
Not what I’ve found from personal experience but things can change (I set up a multi-Desktop machine only once every couple years or so for demos). This was really surprising to me at the time I discovered this because it definitely can affect how the Desktop works sometimes.
Adding a different DE might install a new WM, but that doesn’t necessarily mean that the new WM is enabled when you switch Desktops.
TSU
Well for KDE and Gnome it certainly does ie KWin for KDE, Mutter for Gnome, and you choose your preferred graphical environment at the login screen. (BTW, it is the display manager that you set using ‘update-alternatives’)