SOLVED: Transcoding at some bitrates result in blank green video

[Jasper Michal]

Reverting to 31.0.101.5085 fixed it, thank you! Still not a huge increase in tone mapping performance (compared to transcoding without tone mapping), but none of the GPU engines or CPU cores show more than 30% usage, do you know what might be the bottleneck here?
It could be Re-BAR like you said, especially considering the motherboard only has PCIe 3 which is already bandwidth-limiting, but I'm just guessing.

Thanks for all the help!