didn't want to start a new thread but I have similar problem but with a lot more complicated setup
got two systems
4 way classic titans on 5960x + asus x99 EWS , the one with 4x 16 PCIx and a 3 way 970GTX evga on z87 asrock extreme 11, both systems are water cooled , both have solid hardware ( PSU , RAMs ..etc)
both systems working fine on 3 x asus 4k 31.5 on the same res but using display ports,
recently I decided to get a 3x LG 42 inch 4k running in 12k setup. all flipped to give a total of 6480x3840 res just like the asus setup.
all cables are monster HDMIs rated at 27GBs which is even higher then the 18GB HDMI 2.0 cables
the problem
vsync on , none of the games will work , flickering and horrible micro stuttering , also sudden shutdowns ..
vsync off , horriblae tearing but all are fine which is expected
what I tried
-win7, win8.1 , and even win10 beta with the latest NVidia drivers
-switching and trying all the HDMIs port at the back of the TV ( im a ware of the chrome stuff) . its only HDMI3 on the TV that should give a full chrome 444
- ttian and 970 both fail
active display to HDMI converter , also fail to give the [link=mailto:4k@60hz]4k@60hz[/link]
testing on every single option on NVidia control panel , also fail
single 4k LG is flawless on both systems , it goes nuts only when I go 3x moni system
still digging for solution or hints