"Retina"-style scaling and 60Hz refresh rates reportedly enabled for some Macs.



From ArsTechnica:

OS X 10.9.2 was just released last week, but Apple has already begun testing for version 10.9.3, and the update will apparently come with some goodies for users of 4K displays. According to a report by 9to5Mac, the new update enables HiDPI "Retina" scaling on 4K displays that didn't offer the option in previous OS X versions. It's possible to enable HiDPI display modes on any monitor in OS X with some tweaking, but Apple is apparently interested in supporting Retina-style output on high-resolution monitors by default.

Apple made a big 4K push with its new Mac Pro, which can support up to three 4K displays at once thanks to its twin GPUs and six Thunderbolt 2.0 ports. However, the company doesn't yet make its own 4K Thunderbolt Display—current Mac Pro buyers can add $3,600 32-inch Sharp 4K displays to their orders, or they can bring their own monitors. 9to5Mac's testing was conducted with what appears to be a 39-inch Seiki Digital display, which as of this writing can be had on Amazon for $500 (though it doesn't support a 60Hz refresh rate at 4K).

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