Prorender problem

Something strange is happening while using GPU. See the screenschot. CPU only renders normal, GPU shows only this cube, grayed.

Win10Pro, AMD FirePro W5130M, i7-6820HQ, Blender 2.78

Does anyone have an idea, what Can I do?

First, post your scene file.

Working OK here on W7, blender-2.80.0-git.790cb7799dcf-windows64 (latest) & RPR 2.01 (2/15/19 update), GTX1060, Q M5000, 2x intelX5650