Apple just added external Retina display support in a recent beta of OS X Mavericks 10.9.3, According to 9to5mac. 4K monitors can now run the operating system at a pixel-doubled resolution, like on a Retina MacBook Pro. It could also be a sign that Apple is getting ready to release a long-anticipated external retina display.
Like on the MacBook, the display setting screen will allow you to “scale” the resolution. You can choose between the native 4K resolution or a Retina-like resolution with bigger windows but sharper text. It increases the pixels per inch density.
When it comes to software support, Retina-optimized apps for the MacBook Pro are already optimized for the external Retina displays. It uses the same HiDPI method.
But the most challenging part of supporting external Retina displays comes from connectivity. While Thunderbolt 2 is capable of transferring 20 Gbits per second, Apple’s website only promises a 24Hz refresh rate for true 4K displays with a 4096 per 2160 resolution. Moreover, only recent Retina MacBook Pro models come with Thunderbolt 2, and the new Mac Pro.
Yet, users who installed Windows on their Macs were able to get a 60Hz refresh rate with a 4K display. It could be a software limitation on Apple’s part.
Apple hasn’t updated its display since 2011. The last update was a connectivity upgrade — the company switched from a DisplayPort connector to a Thunderbolt connector. That’s why many have been speculating on an upcoming Retina display.
Apple’s current display supports a resolution up to 2560 by 1600. Yet, doubling the vertical and horizontal lines (5120×2880) would be difficult. These displays could be difficult to produce, expensive, GPU intensive, and hard to drive over a cable. As 4K displays are becoming more mainstream, Apple could choose to make its own 4K display and settle with this intermediate resolution. Late 2013 Retina MacBook Pro and Mac Pro would already support these displays.
Today’s software improvement is an improvement for 4K display owners. But it’s even more interesting when you consider that Apple is also a display manufacturer — an Apple-branded Retina display could come sooner than expected.