Der Pymol users!

I wounder to know if it possible to increase rendering rate mainly at the expense of the GPU usage. At my desktop with core i7 and 6 cpu (12 cpus in the hyper-threading mode) I've spend  ~ 2 hours to render image consisted of ensemble of conformations (~ 30 aligned pdbs) using only CPUs.

set ray_trance mode, 1
ray 3000
png ./1.png

Does it possible to add some loading to the gpu as well?