I have the AMD HD7970 graphics card with latest drivers. I can use Open CL accelerated previews in Vegas Pro 12, but the performance isn't good and I can't use it to encode videos.
The performance I think is still better than CPU only, I'm getting less than 10FPS for a plain H.264 1080P video on OpenCL. What bothers me the most is if I open up GPU-Z I see the GPU utilization never goes beyond 10%, but I can see the reactions and it is definately using it.
As for the encoding, if I click the Check GPU button it says OpenCL is available but there is no selection box for using GPU only or CPU only or both. And when I start the encoding GPU goes active but again, utilization is minimal, like less than 5% in fact.
I am running Windows 8 Enterprise, do you think that is the problem?
also I don't know if related, GPU acceleration in Photoshop CS6 also isn't ideal. It's like 10FPS or something, even for small images. I remember it was smoother with my old GTX 260. but not sure if it was smoother when Ihad Windows 7.
I can't address the Sony Vegas Pro 12 issue but as far as Photoshop goes it probably did perform better the the GTX 260 as Adobe prefers the use of NVIDIA cards and only certain ones of those does it support for CUDA.