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4K/UltraHD and HDMI 2.0 - What you need to know
The information on this page will be essential for installers and professionals who encounter connectivity issues between 4K Sources and 4K Sinks (Displays).
We strongly recommend that you review the material as it will allow most to better understand how to overcome the various EDID and TMDS related issues.
For more advice and assistance, please contact us. We will be delighted to offer our products and services to ensure successful completion of installations involving 4K technology.
Why is 18 Gigabit Speed so critical to 4K?
Cables must operate at the full 18Gbps bandwidth, which is typically needed for interacting and combining 4K/Ultra HD content with HDR (High Dynamic Range) and High-Frame Rates (50/60fps).
HDMI (High-Definition Multimedia Interface) is a proprietary audio/video interface for transmitting uncompressed video data and digital audio data from a HDMI-compliant source device (e.g. DVD & Blu-ray players, gaming consoles) to a compatible video display (HD/4K TVs & Projector). HDMI has become the de facto standard carrier for high-definition home theatre and various other applications, and is now a prevalent standard on high-end graphics card used by gamers, graphic designers and video editors.
While the HDMI connection system has evolved in many ways since it was introduced in 2003, the cable configuration has remained unchanged. However, an alternate configuration was added in v1.4 to support Ethernet and the Audio Return Channel. Other than that, the only changes that affect cables are the increased bandwidth needed for the features introduced with each new HDMI version.
Can existing HDMI cables support the higher bandwidths of HDMI 2.0 Specification?
Yes, existing High Speed HDMI Cables (wire only) will support the new higher bandwidths (up to 18Gbps). HDMI 2.0 specification defined a new, more efficient signalling method1, for speeds above 1.4b limits (10.2Gbps), to allow higher bandwidths (up to 18Gbps) over existing High Speed HDMI Wire Cables.
HDMI Licensing, LLC
https://www.hdmi.org/manufacturer/hdmi_2_0/hdmi_2_0_faq.aspx
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Theoretically a High Speed (Category 2) HDMI cables should support the increased 18Gbps bandwidth requirement of the latest HDMI 2.0 components, especially over a short length of one or two meters. However, this is often not the case due to improper cable termination techniques, poor quality wire and inadequate Quality Control.
Furthermore, cable bandwidth rapidly decreases with length, so even two meters of non-compliant /un-certified cable may be too long for HDMI 2.0 applications. The best HDMI cables exceed these bandwidth requirements, reducing data errors to provide superior audio and video performance.
The maximum theoretical limit (for 18Gbps bandwidth) of a conventional complaint copper wire cable (24AWG) is around 5m. Hi-end cable manufacturer like Wireworld have cable designs (Symmetricon™ & DNA Helix™) that can surpass this limit but at a significant cost penalty.
The only way to achieve a reliable trouble-free connection between a 4K/Ultra HD Source and a Display is to use a HDMI cable/Link that has passed HDMI compliance tests (HDMI 2.0 CTS) and/or certified to meet the 18Gbps bandwidth requirement.