GTX 960 owner here, and on Gnome i use early KMS, so in /etc/mkinitcpio.conf i have:
MODULES=(nvidia nvidia_modeset nvidia_uvm nvidia_drm)
Also, i use in /etc/default/grub under the GRUB_CMDLINE_LINUX_DEFAULT this kernel parameter:
nvidia-drm.modeset=1
You need to run:
sudo mkinitcpio -P
and
sudo update-grub
if you modify those files.
Regarding the /etc/X11/mhwd.d/nvidia.conf i always use:
Option "TripleBuffer" "On"
Option "ConnectToAcpid" "Off"
under Section “Device” instead of the Option "NoLogo" "1"
And if i have to edit the conf file, i always run this commend:
sudo mhwd-gpu --setmod nvidia --setxorg /etc/X11/mhwd.d/nvidia.conf
One thing is unclear to me, what connection port and cable are you using?