System Information
Operating system: Mac OS 11,0,1
Memory: 64 GB
Graphics card: Radeon Pro Vega 48 8GB

Blender Version
Broken: 2.91.0
Worked: (newest version of Blender that worked as expected)

When I render (CPU) big picture in resolution 10630/7087 Pixel it take a long time and the Mac "get to sleep".
If I "wake it up" by log in before the render is done Blender dumps but if I wait until the render is done it's OK.

Exact steps for others to reproduce the error
Render (CPU) big picture in resolution 10630/7087 Pixel and wake it up" by log in before the render is done, let it go for 2/3 of the time.