Dell UP2414 Tiled on 4,1 with EFI 7970


macrumors newbie
Original poster
Aug 10, 2006
Hello everyone,

So I'm working on building a fast 4,1 for my work and one of the things I really want is a 4K display or two, so I picked up a Dell UP2414Q and a 7970 and flashed it with with the proper EFI.

However, when I boot my system the Dell display looks like this

Using SwitchResX I can set each "half" to 1920x2160@60Hz and it works except since the OS thinks it's two separate displays I have the expected limitations.

When I disable display port 1.2 it gives me 1 4K display at 30Hz, and when I boot into windows 8 on this machine I get 1 4K display @60Hz (with DP1.2 enabled) so I guess it's not a hardware problem.

Is there a way to force the system to recognize the display as a single display instead of two halves?


macrumors newbie
Oct 23, 2014
I have been thinking of running almost exactly the same setup, but keep finding little issues like these in lots of forums. It appears no particular setup is foolproof, or at least no one is talking about theirs if they've found one.

Here are some interesting reads. Not sure if they will be of direct help, but worth looking at.

Netkas forum post 1
Netkas forum post 2
Netkas forum post 3

Hopefully you can figure it out! I'm ready to spend the dough because I need this stuff for work, and I think other people could benefit from this info too.

This might be of some help too.

Apple 4K support link

Which mentions a firmware update might be necessary. Have you checked for this?
Last edited:


macrumors 6502a
Aug 8, 2006
I have 7950 EFI with UP2414Q. also found this problem too.

Try everything, every method, so i gave up.

I change from 7950 to GTX680 everything works 4K with 60Hz.

Just suggesting.


macrumors newbie
Original poster
Aug 10, 2006
Glad to hear I'm not the only one with this problem, but apparently there is currently isn't a (software) solution.

I'm considering an nvidia card since CUDA seems to be winning the GPU computing framework war but ideally I like to do it at my leisure instead of being forced to due to a software bug.

With that said will any DP1.2 enabled nVidia card work?
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