The screen is rarely the limit
Modern LED controllers accept HDMI 2.0, DisplayPort 1.2 and SDI on the same chassis. The weak link is almost always the source device, the cable run, or the person who spec'd a 30-metre HDMI cable because it was cheaper.
Cable length is the real constraint
| Interface | Reliable passive run | What to do beyond that |
|---|---|---|
| HDMI 2.0 (4K60) | 5 m | Active optical HDMI, or convert to fibre |
| DisplayPort 1.2 | 3 m | Active DP cable, or DP over fibre |
| SDI (3G) | 100 m on coax | Native strength of SDI |
| HDBaseT | 100 m on Cat6 | Good middle path for installed rooms |
When SDI wins
Broadcast, live events, and anything where the cable has to run 60 metres through a ceiling with no power outlet in the middle. SDI carries one signal, locks mechanically, and does not negotiate HDCP. That last point matters: HDCP handshakes are the single most common cause of a black screen at the worst possible moment.
When HDMI wins
Anything consumer or corporate: laptops, media players, video conferencing codecs. It is the default output on almost every device and it carries audio. The trap is assuming a long cheap cable will work because it worked on a desk.
When DisplayPort wins
Multi-monitor graphics cards, workstations, and any case where you need to drive a 4K wall from a single GPU output with daisy chaining. DP also tends to handle non-standard resolutions more gracefully than HDMI when you are feeding a custom canvas.
What to write in the specification
Name the interface, the resolution, the refresh rate, and the maximum cable length in one line. For example: HDMI 2.0, 3840×2160 at 60 Hz, maximum 5 m passive or 30 m active optical. A supplier who cannot answer that line in writing has not done the project before.