[CentOS] CentOS 7.2, nouveau won't go away

Hi, folks,

   Fully updated 7.2 system. I installed the correct proprietary NVidia
driver (the user's expensive proprietary visualization software won't
run with nouveau), I've put nouveau.modeset=0
rd.driver.blacklist=nouveau on the kernel line for grub2, and even yum
removed the nouveau driver and built a new initrd... which won't boot,
it seems to start and than does nothing, with a black screen, and this
is just while booting, before it goes to graphical mode.

   If I boot the as-built current initramfs, it loads nouveau, though one
of the modules listed if I do lsmod | grep nou shows nvidia, in
addition to nouveau.

   So, in 7, what do I have to do to make nouveau go away? Is it as simple
as creating an /etc/X11/xorg.conf, or...?

    mark