mr_phoenyxx, the problem is that the 1080Ti and Poser are speaking different languages and do not understand each other. The 1080Ti was released in 2017, Poser 11 in 2015. GPU rendering is still relatively new and nowhere near as mature or stable as CPU rendering, and the various cards have gone through major changes internally over time. It could be that the slowdown you've seen is to do with changes in the graphics drivers. It isn't Poser because Superfly has not been updated since the initial release. Octane Render is exactly the same - when I was using it, every time a new round of Nvidia cards got released it would have to be updated to work properly. At least you don't have a new RTX card as they just don't work at all.

So I think that both Poser and the 1080Ti are working, they just cannot communicate efficiently. If your rendering speed is good when using two cards together then that is your best solution for GPU rendering right now; alternatively switch to CPU. The long term solution is for Superfly to get an update (and I hope that it's high on the dev teams list).

----------------------------------------

Not approved by Scarfolk Council. For more information please reread. Or visit my local shop.