How can you use a gpu to process rtas or vst audio effects?

If you have an Nvidia 8 series or above, you can use your gpu with certain plugins which support CUDA, such as some by LiquidSonics. Most VSTs aren't set up to run with CUDA though, and so won't work. Other people have experimented with transferring the workload of the VST to a GPU, but usually the latency becomes so large, it'd be more effective to use your cpu and wait for the tracks to freeze and just run as audio.