DispalyPort doesn't have 20Gb/s support. It tops out at ~17Gb/s. That is enough for 4K 60Hz, but DisplayPort is not Thunderbolt. Thunderbolt is the one with that 20Gb/s support.
I realize that, but the cables are advertised as 20Gb/s.. go figure.
It also isn't just the cable. Driver support is needed also. (although how far apart the Sharp/ASUS monitors are from this shouldn't be much, if at all, all a difference. )
The ASUS is just a re-badged version of the SHARP that Apple is offering from their own store. Both support dual steam mode for 60Hz. We have borrowed one of the ASUS monitors and have it connected to a new Mac Pro here. Dual stream (MST) mode on that display has sync issues with the secondary display stream.
I purchased the Dell 24" and after enabling MST, have similar results. Secondary stream shows sparkles, flickers, occasional drop-outs. Some drop-outs take out both sides of the display for a split second. I'm hoping it's a cable issue, however my new cables did not show up yesterday as I had hoped. Now it looks like a monday thing.
Anandtech reviewed the Dell 24" connected to the new Mac Pro and had similar, although seemingly a bit worse, results to what I have encountered. They also did not have the latest EFI update installed and it is unclear as to weather they were running the system under 10.9.1 or just 10.9 as the systems ship. There is also the 10.9.2 developer seed available and I have downloaded it, but not installed it yet. It supposedly has an updated Dx00 driver package that may address an issue or two here.
Odd the manual doesn't mention the DisplayPort ports have asymmetric abilities.
Which manual? I've used the SHARP PN-K321 in the past, however only on an HP workstation running Windows, and the DisplayPort stream settings are fully functional on both the monitor and PC in that situation. I don't have the ASUS manual to look at, just borrowed the monitor. I'm assuming it's in my Dell 24" manual, but have not looked, easy enough to find without looking at some manual I'll never read. I would *ASSUME* at potentially great risk that the 32" DELL, which seems to be based on the same panel and innards as the SHARP and ASUS displays, also supports dual stream MST mode. The Mac Pro manual, if you can even call it that, has nothing in it, I question its existence.
Apple has a few online support documents that deal with DisplayPort / Thunderbolt displays and 4K. Like this one here:
http://support.apple.com/kb/HT6008
Working and glitching are mostly opposite states.
Indeed. And I expect to have it in working order in the near future. Perhaps with a cable swap, perhaps with an impending software update, or both.
