Tim Hardwick (via Mike Rundle): Several MacRumors readers using 4K displays have described the disappearance of scaled HiDPI resolutions beyond 1920×1080 since updating from OS X El Capitan, leaving their options reduced to 1080p or a non-scaled native resolution of 3840×2160. Monitors with native 1440p resolutions also seem to have had HiDPI scaling options removed. … Continue reading Sierra Drops HiDPI Scaling on External Displays