[Debian-Stretch on macmini-4.1] Can't get X working with nvidia

[Ennio-Sr <nasr.laili@tin.it>]

Hi all!

since I installed new kernels (i.e. 4.9.0 and 4.14.0-0) to be
half-protected against Meltdown/Spectre I was having freezing problems
with X using 'nouveau' driver (never had any problem with older
kernels). So i decided to try the original non-free nvidia driver as
provided by the nvidia-legacy-340xx-driver and relted packages. Now,
after struggling for a couple of days to search the web for a possible
solution to the 'black screen' coming out running startx, I'm curious to
know if there is any of you with the same hardware who found a
workaround and would share it.

Looking at the various logs I can't find any clue. 
Reading <https://wiki.debian.org/NvidiaGraphicsDrivers#configure> I also
consulted the suggested link 'http://askubuntu.com/a/613573/134848' but
as its author worked on a MacBook7,1 whereas mine is macmini4,1 I'm
afraid either I misunderstood his advices concerning the 'setpci -s' (my
values where different) or that patch is not applicable to macmini.

Thanks for your attention, regards, ennio
-- 
[Perche' usare Win$ozz (dico io) se ..."anche uno sciocco sa farlo.   \\?//
 Fa' qualche cosa di cui non sei capace!"  (diceva Henry Miller) ]    (°|°)
[Why use Win$ozz (I say) if ... "even a fool can do that.              )=(
 Do something you aren't good at!" (as Henry Miller used to say) ]