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 signaling method, for speeds above 1.4b limits (10.2Gbps), to allow higher bandwidths (up to 18Gbps) over existing High Speed HDMI Wire Cables.
Does HDMI 2.0 require new cables? No, HDMI 2.0 features will work with existing HDMI cables. Higher bandwidth features, such as 4K@50/60 (2160p) video formats, will require existing High Speed HDMI cables (Category 2 cables).