Anyone runs Linux with Nvidia GPU capabilities?

Is the exact message more like, "nvidia GPU doesn't support OpenCL" or something like that?  The easiest way to let us know for sure is to post the GPU detection messages exactly from what you see in the event log when BOINC starts.

All distros tend to do things a bit differently so you might find that the OpenCL libs are in a separate package from the video driver.  If you don't see the detected version of OpenCL that the card supports in the startup messages, you may simply be missing the OpenCL libs package.

I use PCLinuxOS which is an RPM based rolling release distro that suits me fine.  I used to use a lot of nvidia GPUs (550Ti, 650, 650Ti, 750Ti) but now that there is only an OpenCL app, I've retired them all except for the 750Ti.  Their CUDA performance was very good but very poor for OpenCL.   You should find that the 1070 you mention will perform quite well, from all accounts.  From what I've read, the recent higher end nvidia cards do very well as long as there is enough CPU support available when needed.  They are simply far too expensive for me in Australia.

 EDIT:  I just looked at your list of hosts - I should have done that before :-).

I see you now have a new host created after your earlier message that is now churning through GPU tasks under Linux.  Perhaps you'd like to tell us exactly what the problem was?  :-)