Windows 8.1 with extended desktop looks to be broken. The text is either blurry on my Surface Pro or on my monitor. If I boot while the monitor is plugged in, then the Surface Pro text is blurry. If I boot without the monitor plugged in, the Surface Pro text is crisp. When I plug in the monitor, the text on the monitor is blurry _and_ the task bar isn't sized correctly (i.e., the text for the time/date is oversized and the icons are tiny).
In either case, I can get crisp text on either the Surface Pro or the monitor, but not both. I'm using the default settings for Windows 8.1 (font scaling) and extended mode. I really want to use DPI scaling (the default setting) because the Surface Pro screen resolution is far too high to not use DPI scaling.
This problem only appears when running the desktop. Apps look great on both at all times.