Does anyone have the 24" Dell 4k, thinking about getting that one if it dips below $1k, and would like to know if it plays well with the nMP.
" ... The same isn’t true, unfortunately, for other 4K displays on the market. Dell sent along its UltraSharp 24 Ultra HD display (UP2414Q) for this review, and unfortunately that appears to be a display that’s not supported by the Mac Pro/OS X at this point. You can get it working in SST mode at 3840 x 2160 30Hz, but forcing MST results in a 1920 x 2160 display spread across both tiles with a mess of garbled colors. ... "
http://www.anandtech.com/show/7603/mac-pro-review-late-2013/11
In conclusion of same review...
".... r. It turns out there’s a very good reason Apple only offers the Sharp PN-K321 via the Apple Store: 4K display compatibility under OS X is still a bit like the wild west at this point. I do expect that Apple will quickly fix things (and likely offer their own 3840 x 2160 and/or 5120 x 2880 panels) in the near future, but early adopters beware. ... "
http://www.anandtech.com/show/7603/mac-pro-review-late-2013/15
If only interested in 4K at 30Hz it is far less of a 'Wild West'. That is far more likely more universal. The work-arounds for 60Hz and synchronously sending two "halves" of the 4K screen to a monitor is a where the 'Wild West' kicks in.
If waiting on a Mac Pro order to ship or thinking about buying Mac Pro later it is worth not getting the 4K display early. This might clear up by April but definitely should be more info of this is a long term or short term issue by then.
The fact that "oops you might have to buy the monitor from Apple" probably doesn't' put this on their high priority fix list. I would expect the Dell 31" monitor to work before the 24" one. At least the 31" one is also a Sharp panel with some modifications wrapped around it.
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How does a 4K monitor stress the CPU?
Dependent upon how many objects put on the screen and the split of the modeling computation workload. It doesn't have to ( more MS Word windows ) but would depend upon the app.