HDMI 2.0 Cables don't exist! You might be shocked to read that statement especially if you've been on sites like Ebay or Amazon and other unscrupulous retailers where it appears you can buy an HDMI 2.0 Cable.
HDMI 2.0 is an equipment specification, it does NOT change HDMI cables or connectors in any way, all High Speed HDMI cables support HDMI v2.0, even older HDMI 1.3 category 2 cables, if you've been sold an HDMI 2.0 Cable you've been duped!
So what is HDMI 2.0? HDMI 2.0 defines some new features and higher bandwidths that support newer modes, some of the new features are:
• 4K@50/60, (2160p), which is 4 times the clarity of 1080p/60 video resolution
• Up to 32 audio channels for a multi-dimensional immersive audio experience
• Up to 1536kHz audio sample frequency for the highest audio fidelity
• Simultaneous delivery of dual video streams to multiple users on the same screen
• Simultaneous delivery of multi-stream audio to multiple users (up to 4)
• Support for the wide angle theatrical 21:9 video aspect ratio
• Dynamic synchronization of video and audio streams
• CEC extensions provides expanded command and control of consumer electronics devices through a single control point
All of these features are supported by your existing High Speed HDMI Cable or High Speed with Ethernet Cable, you don't need to buy a new cable so don't get misled into believing you need to buy an HDMI 2.0 Cable as HDMI 2.0 does not define anything new with regard to the HDMI cable or connectors.
As technology improves it is the electronics that improve the signal rates attainable on cables not the cables themselves, the situation with HDMI 2.0 is exactly the same, take for example the telephone system, 20 years ago it was a struggle to get 56kbps per down the copper cable, then ADSL got a few Mbps on the SAME copper phone cable, now VDSL can get 10s and even 100s of Mbps down the same copper cable.
HDMI 2.0 has defined a new more efficient signalling method which supports up to 18Gbps, when using HDMI 2.0 equipment all existing High Speed HDMI cables (without built in chipsets) will also support this data rate.
In summary, there is no such thing as an HDMI 2.0 Cable, all existing High Speed, High Speed with Ethernet and Category 2 Cables support HDMI 2.0 features and data rates of 18Gbps in the same way that they support 10.2 Gbps when used with HDMI 1.4 equipment.