Does Redshift support multiple GPUs on one machine?

Yes, Redshift is configured to use up to 8 compatible GPUs per session on your machine by default. It can also be configured to use only a select subset of GPUs on a given system.

These GPUs can be of any combination of different generations and memory configurations (e.g. 1 GTX TITAN + 1 GTX 1070). 

Using a render manager (like Deadline) or using your 3d app's command-line rendering, you can render multiple frames at once on systems with multiple GPUs, which helps ensure the GPU resources are used as efficiently as possible. 

Review this FAQ for more information on hardware considerations for Redshift.