Driving a 5K Apple display

There have long been rumors of Apple releasing a standalone, large screen retina display. With recent reports of limited Apple Store inventory of Thunderbolt Displays, the rumor mills are back in business, whispering the possibility of a 5K 27″ thunderbolt display announcement at next week’s WWDC.

From this MacRumors post:

Only the late 2013 Mac Pro, late 2014 or newer 27″ Retina 5K iMac, and mid 2015 15-inch MacBook Pro with AMD Radeon R9 M370X graphics are capable of driving 5K external displays, however, and each setup requires using two Thunderbolt cables per display. The lack of support is due to bandwidth limitations of the DisplayPort 1.2 and HDMI 1.4 specs on current Macs.

DisplayPort 1.3 has increased bandwidth, but Skylake-based Macs with Thunderbolt 3 will not support the spec and Intel’s next-generation Kaby Lake processors on track for a late 2016 launch will not as well. Apple could opt to release a 4K Thunderbolt Display instead, but supply chain considerations make this unlikely, so the company’s exact plans for the future of its standalone display remain to be seen.

In this post, John Gruber posed the question:

A 27-inch standalone retina display will be a genuine finally. If they announce it at WWDC, the crowd will go nuts. But just how they’ll drive it is a fascinating question. Using two Thunderbolt cables would be clunky. Maybe one cable that forks into two Thunderbolt adapters at the end?

All that is background for the linked post, where Rene Ritchie explores the tree of possibilities for driving a 5K display.

I do find it fascinating that we’ve come to a fork in the road where we have everything we need to add in a 5K display, with the exception of a single port to drive it.