My dad bought a new Mac Pro along with a host of pro peripherials (including a 4K display) for his multimedia work and asked me to get him a few Thunderbolt 2 cables. However, when I browse for them online on Apple's site and elsewhere, it's not clear if they're all Thuderbolt 2 compatible, meaning they can take advantage of the full 20Gb/s TB2 speeds. It's a little confusing. If I get a new TB cable from Apple, is it a TB2 cable? Will it work with the 4K video bandwidth?