I have the found following problems with boinc installation.

Boinc manager quits on its own yet keeps running.

Kill boinc process using top but on opening new boinc, boinc tells me boinc is still running.

Suspend boinc and come back to find boinc is running.

Abnormal operation. Why?

GNU/Linux [Ubuntu] 12.04 Kernel:3.2.0-52pae
Gnome 3.4.2
AMD Quad Core 9600
4Gb Ram.
Boinc version 7.0.27

BOINC consists of several parts, most importantly a client and a manager. The manager part is only a graphical user interface that allows you to command the client easier. The client can easily run without the manager.

Therefore, when you exit BOINC Manager but choose that the tasks can continue when you exit the manager, that's exactly what will happen. BOINC Manager will exit, but the client and the science applications will continue to run.

This was done to prevent a crashing BOINC Manager from taking the running client --and thus the science applications-- with it. Which is what you see here. You see BOINC Manager crash, but the boinc-client binary and the science applications will continue to run (check in Top).

If you want to kill the boinc-client in a controlled way, read up on the BOINCCMD command line tool. Use boinccmd --quit to stop the client completely.
Or restart only BOINC Manager (boinc-manager) to restart the GUI.

You can check in stderrgui.txt if there's information about why BOINC Manager crashes, and then tell the package manager maintainers about it (and ask them to update to 7.0.65, the present recommended). It's their BOINC version, seeing how you use 7.0.27. That version was never recommended from Berkeley (7.0.28 was).

Or you can update to Berkeley BOINC, as it's built on Ubuntu.

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