Fear The Sleep 4K Darkscape Wallpaper.
3840 X 2160
I admit this wallpaper is scratchy but I think it looks really good on a Matte Monitor. I added a pic of the original before I put the VooDoo on it. You can see what I had to work with, just click the arrow in the preview.
But ya know its all about doing what you can to these images to try and make something better then the original.