This was a quick modeling job of a "Lightsword" smh It was modeled in filmer and then uv unwrapped and only added limited texturing to it as it was my laptop so baking at 4k plus would have been a nightmare on it. The model was exported as an OBJ file, tried FBX but portions of the model despite being one piece was missing portions. https://youtu.be/NDXkWCozP3o

I am not sure what is going on here but this is Blender 2.8 after I took my created project in Filmer over to it for a comparison render. As you can see it is like my laptop processor and gpu decided to have a party and invite random strangers to help render. The auto detect says 4 but yet you can see there is definitely more than 4 going to work on the render. Not sure if it is cause the project was created in Filmer and then brought into 2.8 for a comparison render but I have never seen that many tiles rendering all at once laptop or desktop. Now that I think about it may be 2.8 leaves a tile outline around the tiles still to need denoised (think that may be what is going on) here is a link to the larger image https://i.imgur.com/iVlf1Nh.jpg