If you would like to see your GPU at 99% down load this file unzip it, run the project file, and follow the built in instructions on the screen. You might want to clock time the two runs. The first run is with the GPU and since you have and older CPU if it can feed the GTX660 Ti fast enough you should see near 100% utilization of the GPU. The second run with only the CPU will take a long time maybe it will seem like forever!
The file is around 200 MB
Thanks will check it out
OK, that test project export proved the GPU is properly enabled.
Huge time difference with and without Mercury Engine GPU processing, and GPU load maxed out at 81% with MPE GPU enabled.
Now I realize that the other GPU accelerated effects, such as Warp stabilizer, may have nowhere near the GPU performance boost as that export render.
Next step: new CPU/MB/memory. $$$.