Hello !

RS wrote:

Regarding making the change in my Account (on the website): I have BOINC
running on several machines now. I use the same account for all of them.
Only one is Hyperthread capable.  I have not set up the different computers
on the website ... should that have been done ? Does your advice still stand

Yes. If your computer has only one CPU, the boinc starts the client only at one CPU.
If it is configured, like f/fgeorge has written, and you have two CPUs (like on Hyperthreaded systems), boinc will start the science app on two CPUs.

Lars