Well the task manager for example, the header is rendered per pixel, the rest of the window is a blurry mess. File Explorer window scales with DPI setting but for some reason the fonts still render at 4k pixel size even at 175% scaling making it very hard to read. Chrome looks like its rendering at much lower resolution then blowing back up. Resizing a busy window chugs my GTX 980 yet the Haswell integrated GPU on my MBP 13" handles 5120x2800 pretty well on OSX.

Why can't they just supersample the user-selected resolution then shrink back down to 4k like OSX? Everyone already has retina assets for their app.