Have you seen the GPU computing benches and BOINC results of the 750 Ti little monster ?
It seems NV has tweaked it well for GPU Computing.

On GPUGrid it doesn't seem to work yet. Apparently they need to wait for CUDA 6 with explicit Maxwell support.
But on Einstein some results show 8500 s for BRP5 and 3100-3400 s for BRP4G ! That's impressive !