Hey everyone!!

So I'm a student and our university has a beast of a machine running 4x GTX 680s. We originally bought it to test Octane and other GPU engines for our rendering pipeline, but I'm interested in seeing how well it performs OpenCL in regular Houdini Apprentice. I'm just getting started with Houdini so I don't know my way around real well yet, but I did find the OpenCL toggle under the gas node for the PyroFX explosion, but I was unable to click it.

Is the OpenCL option limited in the free version of Houdini, or am I just missing out on something? Pretty much, how do I get the most out of these cards in Apprentice? Also the cards aren't set up for SLI, is that going to affect it as well?

Thanks

You want to check the OpenCl checkbox under Pyro Solver / Advanced tab. If you were looking inside the pyro solver, those nodes are ‘locked’ because they are inside the pyro solver otl. They should be referencing the parameter up on the Pyro Solver. Also, I'm pretty sure it's not disabled in apprentice. It doesn't currently use more than one card for simulation, so your extra GPUs won't give it any boost. There's an environment variable (not sure what it is) that you can specify which card to use for OpenCL calculations.