WIN 10 latest GTX 780 DELL Xeon System
Short description of error
I am rendering a scene in 16K resolution. In the beginning it was fine. Then I realized slow-downs in the transparent area of the picture.
When I move the window the tiles start to speed-up dramatically and render in a speed the empty area as expected.
When I stop moving the window it slows-down extremely. When the tiles start to render geometry the CPU performance in the task manager is at 100%.
When it comes to the transparent areas the CPU slows down dramatically till I move the window again.
But also here I realized now that the render speed in the geometry areas will slow-down if I keep the window in foreground.
When I close the window to background the speed goes up to 100% then.
But once it will reach the transparent area again in background the speed slows down to around 30%.
Crazy. I can't say if this is the size of the rendering. The scene render takes around 15GB of my RAM (32GB).
Attached you'll see screenshots of the CPU effect,
Exact steps for others to reproduce the error
I can upload the complete scene if necessary. The render will