Hi!
I have too identical laptops, both XPS 9550 with 960M on them. On my old 9550 i got all the option in photoshop with Use graphic processor to accelerate computation shown in the phothops and its missing in new the other laptop. I use same graphic drivers and I choose to use Nvidia 960M graphic card for Photoshop and Sniffer.
Please let me know how to enable this option as I run out of ideas and photoshop is a bit laggy without it.