texture vs solid color, performance difference?

How much of a performance difference is there between lets say 512x512 textures vs colors?
Does how a texture look make a difference? Like if a texture has 2 colors in it, or 200, does it matter since its still a texture? Trying to optimize a bit. Thanks!

A texture can’t have 2 colors, or 200. The days of indexed colors are long gone. Use compression (such as DXT or PVRTC depending on platform) where possible.