How can I render a very large image in cycles? I want to render a image in 20000x20000 pixels. But I get the error GPU out of memory. My Peak in constantly getting higher. It starts at 280M, after a hour it is 2000M.

I have a GeForce GTX 1060 6GB. I uploaded my model via an OBJ file it. The Blend file is 90 mB. I have save buffers on to reduce the memory usage . 

Has someone a idea how i can still render this image in 20000x20000 pixels? or is this just not possible. 

Thank you in advance.
Use the "Precise Render Border Adjust" addon. 



It allows you to easily split the render into smaller tiles which you can combine later in an image editor.



When rendering just make sure that cropping is enabled, otherwise blender will try to construct the complete image, which may freeze or crash the program upon completion or while exporting.