To have a real benefit you have to buy the extension (GPU-X), if your motherboard can't handle more than one card and one or two more graphic-cards. If you have this you are equiped to use Octane-renderer with your exported Poser scenes (without textures/shades and displacements). The advantage is, texturing is easier with Octane then with Poser ;) 

Ahh - and don't forget: You have to use Nvidia Grafic-Cards with a lot of memory. GPU-Memory is important while using Octane if you want to render high-res and/or complex scenes.

Add this together and Octane is not anymore a "renderer that poser guys can easily affort" :)

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