It uses a 6 pin connector, and everything else on the mac works with it, including openGL display inside cinema 4d. It worked fine on the PC running everything fine + octane. That's why we were confused as to why it stopped working only for octane when moving it to our mac.

Sure, I'm running OSX 10.9.5

I'm trying to get octane working on my mac pro (with nvidia quadro k4200 and latest cuda drivers and toolkit) and can't get octane to see the graphics card. The standalone version of octane comes up with a message saying 'no CUDA GPUs' and when I look in the preferences it doesn't show the card ...