The 4K HDMI Cable rip-off: What You Truly Need to Know About HDMI 2.0 and Ultra HD Cables
Ever since Apple announced their Mac Pro with four times 4K Ultra HD support the term "4K" or "Ultra High Definition" became increasingly popular. Today a whole industry is mad about the new 4K hype and is offering 4K TV sets for home cinema, 4K displays for personal computers and – of course – things like a 4K HDMI Cable. But do you really need that?
4K – Technical hurdles for HDMI Cables
Attention, alphabet soup! 4K, 4K2K, Ultra High Definition, Ultra HD, UHD, Quad Full HD, QFD, 2160p: Everything means the same! Namely next generation HD-TV (let’s call it “4K” to keep it simple) with a maximum resolution of 4.096px x 2.160px = 8 million pixel = four times Full HD resolution. Of course these large data amounts require appropriate hardware.
Not only the TV set must support this ultra high resolution (which is usually done through sheer size), but also other components such as graphic cards and software (drivers) must handle these huge amount of information. Especially 4K ready HDMI cables are key as the serial interface between the 4K signal source and the high-end television set.
Does every HDMI Cable support 4K Ultra HD?
To make it short: No, not every HDMI Cable supports 4k. But luckily most cables which you can buy today support HDMI 2.0 or HDMI 4k already. Just make sure they are properly classified as HDMI High Speed cable.
After the version numbering for HDMI cables has been dismissed a few years ago, HDMI cables are today only classified in either Standard HDMI cables or High Speed HDMI Cables. Both types differ in their maximum transfer rate (i.e. bandwith):
- Standard HDMI Cable: 1,782 GBit/s (74,25 MHz × 8 bit × 3, Type A)
- Highspeed HDMI Cable: 8,16 GBit/s (340 MHz × 8 bit × 3, Type A + C)
As you can see HDMI High Speed cables provide a much higher performance than Standard HDMI Cables. Luckily most of the HDMI cables which you can buy in stores today are High Speed HDMI Cables by default. Watch out for the term HDMI High Speed on the cable itself or on the HDMI cable packing:
HDMI High Speed was introduced with 4k in mind. All HDMI cables that carry the HDMI High Speed Logo do support the HDMI 2.0 Standard and can transmit ultra high resolutions with 2160p @ 24 Hz (=4k).
The HDMI Licensing Org. confirms this explicitly:
In return this does mean that HDMI cables which are not explicitly called “High Speed” cables do not ultimately support 4K resolution.
Do HDMI High Speed Cables Provide Enough Bandwith for HDMI 2.0?
Up to now HDMI High Speed cables support a maximum bandwith of 8,16 GBitps. HDMI 2.0, however, requires 18 GBitps. So how is that done? The HDMI Organisation provides the answer:
HDMI 2.0 specification defined a new, more efficient signaling method, for speeds above 1.4b limits (10.2Gbps), to allow higher bandwidths (up to 18Gbps) over existing High Speed HDMI Wire Cables.— hdmi.org
This means: When you buy an HDMI High Speed Cable today you can be sure that it supports 4k and tomorrow’s high bandwidth requirements of HDMI 2.0.
How do I recognize a high Speed HDMI Cable?
If you want to make sure that your HDMI cable supports Ultra HD 4K resolution, you have to look for the HDMI High Speed Logo on the cable’s packing.
The cable itself normally does not carry the logo but should rather read the claim “HDMI High Speed”. If you want to be 100% sure you might want to shop a new HDMI cable with explicit HDMI High Speed support.
Since all HDMI cables provide the same display quality you don’t want to worry too much choosing a new cable. As long as it carries the high speed logo and has a fair price, everything is fine!
HDMI Versions vs. HDMI Cable 4K
Full 4K support was introduced with HDMI version 1.4. However, you can only be sure with cables certified as "High Speed" to support the high bandwidth requirements of HDMI 2.0. Cables classified Version 1.3 mostly don't work for HDMI 4K functionality. The following list will give you a rough orientation.
- HDMI cable 1.0 – 1.2 – no 4K Ultra HD support
- HDMI cable 1.3: Probably no 4K support depending on the cable
- HDMI cable 1.4: 4K support very likely, but not guaranteed
- HDMI High Speed Cable: 4K Ultra HD support guaranteed
Conclusion: No need for a 4K HDMI Cable if you choose High Speed
Don’t let you fool by shops or cable merchants with expensive HDMI 2.0 Cables or “4K HDMI Cables”. There is no such thing and there never will be! Just go for a reasonable HDMI High Speed Cable and save your money. High Speed Cables provide 100% compatibility for now and for future HDMI 2.0 contents. The display quality is all the same. You don’t need any new fancy cable hardware.