What a frustrating situation.
Buddy of mine bought that new 12" Macbook with the USB-c port on it and has no problem using the display @ 4K. I went and bought a refurb immediately expecting it to just work, but no dice.
I'm running El Capitan on a MacBook Pro (Retina, Mid 2012) which has the nVidia 650m card, and simply get No Signal.
I have used this laptop on multiple other Seiki displays (50/55" 4K) with no problem. The only way I can get it to work AT ALL is to use firmware Seiki distributes for the 50", AND I have to use a mini-display port to HDMI adapter... that is to say that the native HDMI port does not work at all with this display. The adapter I have is the MacAlly MDHDMI4k, which is specifically designed for 4k.
I have installed SwitchResX and created a custom profile, etc. but nothing is working.
What I have noticed is one difference between this display and the larger one - the EDID.
On the larger display you have a block:
EXTENSION EDID BLOCK 2
DID-EXT: Display ID Extension:
(only partly interpreted)
DisplayID version........1.1
DisplayID Block Type = Detailed Timing Block type 1:
Detailed Timing #1 in Block
Mode = 3840 x 2160 @ 30.000Hz
Pixel Clock............. 297.00 MHz Non-Interlaced
Horizontal Vertical
Active.................. 3840 pixels 2160 lines
Front Porch............. 176 pixels 8 lines
Sync Width.............. 88 pixels 10 lines
Back Porch.............. 296 pixels 72 lines
Blanking................ 560 pixels 90 lines
Total................... 4400 pixels 2250 lines
Scan Rate............... 67.500 kHz 30.000 Hz
Is non-default Mode
Sync: Digital separate with
* Negative vertical polarity
* Negative horizontal polarity
DisplayID Block Type = ASCII String:
SwitchResX
That seems to make all the difference. Both displays have ALL of the same data in EDID block 1, as well as the exact same data in the Monitor Description blocks.
Looks like something was just left out on these. Guess that's why they are discontinued and have had their firmware removed from the web.
Really appreciative to any suggestions others may have.
Thanks,
- MB