I see this has been a problem before but I thought I might report it anyway.
I am unable to render an image with the denoiser turned on - what am I doing wrong?
It happensA weather I use a Principled shader or the RPR Uber shader.
My system:
Mid 2010 Mac Pro Tower.
32 GB Ram
Graphics card: AMD (from MSI) Radeon RX 580 - 8 GB
macOS 10.13.3