FumeFX 7.5 delivers speed improvements of 2× to 5× using NVIDIA CUDA, with automatic fallback to CPU if GPU memory is exceeded.
If you are unable to use the trial, consider these alternatives: FumeFX Free Download
Sitni Sati, the developer, provides a trial version, which is the only legitimate "free" method for accessing the full, current version. The trial license is valid for 30 days. Limitations: FumeFX 7