Tested in Retroarch 1.8.4 witch Vulkan and OpenGL. Windows 10 x64. Nvidia GTX770.
Software Framebuffer: On, Internal GPU Resolution: 8x, Texture filtering: nearest, PGXP operation mode: Memory only, PGXP vertex cache: Off, PGXP perspective correct texturing: On, (the others parameters all default)
I’ve tried also “Memory + CPU”. But it makes strange artifacts that way. I think it must be some kind of Nvidia setting, but I don’t know what.