4K displays push the boundaries of PCs today and you want to push more than one.
First I wonder if the current issue is simply a configuration issue. Do you use a combo of onboard and graphic cards? If so, you may need to not use the onboard or it's simply a configuration issue. I find a lot of folk are not conversant about Windows display setup. I can't be specific since each setup varies. Get someone in there to review the settings.
OK, to drive 4K requires a machine with some high powered CPU and GPU. I'm going to peg this very high so why not some laptop with the 1050 GPU and HDMI 2.0? http://forum.notebookreview.com/threads/list-of-portables-notebooks-laptops-tablets-with-hdmi-2-0-for-4k-60hz.778329/ is dated but gets us going. From this you may remove the old DVI display and use the usual HDMI 2.0 splitter to drive the 2 4K TVs.
I am the Worship Leader at my church and we are updating our media capabilities. I need a computer for my Church that can handle three or four monitors.
- Main Monitor
- Two monitors on the stage. HDMI 4k LCD(Duplicate images, so a split signal is okay.
- One Monitor in back of Room - DVI
Right now, we have an old computer that is only sending to 2 total monitors at a time. We have the On-Stage monitors both connected via an HDMI splitter running from a single HDMI output. However, the computer only recognizes a single monitor and so we are only showing on one. They are both connected properly because when we unplug the working monitor, the other one starts to work.
The monitor in the back is DVI, and while our graphics card has three separate outputs, (1 VGA, 1 HDMI, 1 DVI) it is only outputting as mentioned below.
The computer is old and can barely run our presentation software anyway, so we are upgrading the entire rig. What do I need to do this?

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