Operating system: win7 SP1
Graphics card:geforce GE610 DX11
Broken: 2.79.6 ( but i tried with the latest build and the problem still appears
(example: 2.79b release)
(example: 2.80, edbf15d3c044, blender2.8, 2018-11-28, as found on the splash screen)
Short description of error
the best thing is an image and a blend ;)
EDIT: i have to mention the mesh has no overlapping polys and all normals are properly oriented
The problem occurs when in render mode in 3D view. normal artifacts are also visible on the external round part of the tower. The strange thing is that those artifacts change when moving the object in object mode, or the whole mesh in edit mode.
The sharp marked edges change things in artifacts appearance/position.....
As the 2.79b don't have the AO node ( but an AO shader ), those artifacts don't appear.
As a conclusion, this bug wouldn't be a big problem if it were only visual in 3D view, but those artifacts also appear in baked AO and final renders.
Hope i can help making blender better :))
and also to hear from you soon 📦
Exact steps for others to reproduce the error
Based on the default startup or an attached .blend file (as simple as possible).
just open the blend, move nothing and switch to render mode in 3D view.