cuda in PS isn't all that even with "the hack" (not all gpus are qualified
Photoshop CS5: CUDA
Maddeningly, Photoshop CS5 still does not support any native CUDA-accelerated functions, leaving us in the same boat as After Effects...until we realized that some plug-ins for Photoshop actually use CUDA. Sweet! When we found Digital Anarchy’s Beauty Box Photo plug-in, it was love at first sight.
it does use openGL though without any limitations.