Hello Jayburd, thanks for joining the Intel Community.
Thanks a lot for the information provided.
I was able to check the information from the TPS pag22 and I would need to request information on this since the NUC should be capable of supporting 2 monitors at 3840x2160 @ 60Hz.
Could you please attach the DX Diag report from your system? (Start -> Run -> dxdiag -> Save All Information).
Have you tried using other cables?
Please let me know.
Thank you Sylvia. Here is the content of the file.
I have indeed tried a different cable but it feels like it is not a cable issue. Either monitor with their cable can connect to either one of the mini DP port on the nuc and get 4x2k @ 60Hz. The problem only occurs when both monitors are connected
DxDiag.txt.zip 12.3 K
I was reading the release notes of 18.104.22.16856 graphics driver in the Graphics forum. Quite a few issue were related to 4k display issue. Thinking out loud, is the problem I experienced possibly a driver issue?
Has there been any update to this issue? Is there more information that I may be able to provide to help you troubleshoot the display issue? Thanks!
Jayburd, I'm still waiting for information. We have escalated the issue to the Engineers.
Can I ask what cable you're using? The only Mini-DisplayPort to HDMI 1.4 cable I was able to find on Amazon.com (and Amazon.ca) that can do 3840x2160 at all can only do 30Hz. I only have one monitor--a TV actually, which has two HDMI ports at the back labeled "4K 60Hz"--and since you've just confirmed the 5I5MYHE *can* do 60Hz (at least with only one monitor hooked up), then obviously the problem I'm having is the adapter.
I use mini DP to DP cables to connect the NUC to Dell 4K monitors.
Assuming your TV is HDMI 1.4 as you mentioned, 3840x2160 @ 30Hz is the maximum resolution supported. HDMI 2.0 can support 4K @ 60Hz. In order to get 60Hz with HDMI 1.4 I think you need to connect both ports to your TV. I imagine the NUC will recognize the TV as two independent 1920x2160 displays when you hook up both HDMI ports? I am interested in hearing how it works for you, please post back on what you are able to accomplish.
Thanks for the feedback. I've discussed this with some people at a local computer store, and they also concur that typically if you want 60Hz at 4K with a "standard" monitor, you actually have to use a pair of cables. I guess the mystery is whether my TV will properly sense and support that setup (it's an LG 40UB8000). I haven't yet found any spec sheet that mentions whether it supports HDMI 1.4 or 2.0, but the presence of the two HDMI ports labeled "4K 60Hz" gives me a little bit of hope. I've ordered another of the MiniDP-HDMI 1.4 cable I already have from Amazon.ca, and will post the results as soon as I receive it.
OP, any luck making it work? Looking to pick up a NUC for a dual 4K setup myself.
To follow up:
I received my second cable from Amazon. After getting some weird / corrupt display during my initial setup attempts...I'm not so sure it's actually working. What I mean is, I've got both cables hooked up to the HDMI ports at the back of my TV labeled "4K 60Hz", but I'm not sure whether the TV / the hardware / Windows are all supposed to figure things out by themselves.
Windows shows it's detected another TV that can also do 3840x2160, but the second one works independently of the first. What I mean is, it seems to be extending the desktop to the TV's other HDMI input, and I can see *that* display if I switch to the other HDMI input on my remote. Obviously that's not how it's supposed to work.
I messed around with Windows settings (I'm on 8.1), and I've "merged" the displays using "Duplicate desktop on 1 and 2". The TV doesn't say whether it's running at 60Hz, and mouse movement is still a little jumpy. However, *something* did change--Metro apps used to get extra-large, in that they all seemed to be sizing themselves as if I was running at 1920x1080. They're now sizing themselves so they make better use of the full 3840x2160 real-estate. I have no idea whether this is related to the fact that I now have two wires going to the TV (doubtful), or that I've merged "both" displays into a single one--but I had been running the NUC on this TV for well over a month now, and this is new behavior--can't just be a coincidence.
FWIW, these are the cables I'm now using in pairs: http://www.amazon.ca/gp/product/B00DOZHL82?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
One thing I'd like to get cleared up is that this is a MiniDP 1.1 / HDMI 1.4 active adapter, and I'm getting conflicting reports claiming that it needs to be MiniDP 1.2 (not 1.1). I wouldn't mind getting another pair of cables, but not if I don't get better assurance that this will solve my problem. I'm not convinced my TV is supposed to be able to sense the two cables and manage both inputs as a single display (is this something that's part of the HDMI spec? If not, I'm guessing I'm SOL)...
The TV is an LG 40UB8000. Both cables (going from the adapters to the TV's inputs) are HDMI 1.4.
DP 1.1/HDMI 1.4 doesn't have the capacity to carry 4K@60HZ.
I never tried to get a pair of cables to do the trick, but one explanation would be your TV has HDMI 2.0 and the manufacturer figured it's no longer necessary to include the function.
Anyway, two times 1920x1080 doesn't give you 4K.