Thunderbolt 2 vs 3

Discussion in 'Mac Basics and Help' started by MacBH928, Dec 6, 2016.

  1. MacBH928 macrumors 68030


    May 17, 2008
    I want someone to explain to me what are Thunderbolt 2 is used for? I know its to connect docks with multiple ports but at 20Gbps , in what case scenario do I want a Thunderbolt 3 with 40 Gbps?

    Apple includes 2 TB and 2USB on the 2015 MBP , so it must be popularly used to include 2 of them.
  2. JohnDS macrumors 65816

    Oct 25, 2015
    The thunderbolt ports on the Mac also double as mini-display ports to connect an external monitor. You can get thunderbolt to VGA, thunderbolt to DVI and thunderbolt to HDMI adaptors.

    If your computer does not have an ethernet port, you can get a thunderbolt to ethernet adaptor.

    Thunderbolt ports can be used for computer repair and diagnostics using Thunderbolt Target Disk Mode:

    Unlike USB, you can also daisy-chain devices on thunderbolt.

    Quite frankly, though, from a practical standpoint, thunderbolt is rarely used and has been eliminated from the new MacBook Pros in favour of USB-C. There are few thunderbolt peripherals, and they tend to be expensive, as are the cables. USB3 has become the de facto standard for peripherals and USB-C will likely supplant it, so I think thunderbolt, like Firewire before it, is a dead end.
  3. Enigmaticland macrumors newbie

    Nov 3, 2006
    While Thunderbolt 2 ports used the same shape and form the mini DisplayPort spec had, Thunderbolt 3 uses the same shape and form the USB-C spec has, so the new MacBook Pros have USB-C/Thunderbolt 3 ports. Unlike FireWire, Thunderbolt 3 is widely used and is being included in lots of the most-recent PC hardware, so I don't think it will suffer the same fate.
  4. JohnDS macrumors 65816

    Oct 25, 2015
  5. mfram macrumors 65816

    Jan 23, 2010
    San Diego, CA USA
    Thunderbolt has not been eliminated in the new MBPs. It's actually been updated to Thunderbolt 3. Thunderbolt is faster than USB 3.1.
  6. theluggage macrumors 68040

    Jul 29, 2011
    Well, one example is the new LG 5k Thunderbolt display - a 5k display actually takes about 30 Gbps of bandwidth (equivalent to 2 DisplayPort 1.2 cables) so Thunderbolt 3 should (in theory) leave you with enough bandwidth to daisychain an Ethernet adapter or a hard drive from the display, and still have a '1 cable docking' solution. USB-C can't cut this (until GPUs and displays start supporting DisplayPort 1.3) - you'll notice that the LG 4K display, which is USB-C not Thunderbolt, can only support old, slow USB2 speeds on its USB ports.

    Another use for Thunderbolt 3 would be high performance external disc drives such as superfast SSDs or large RAID arrays for tasks such as high-res video editing - but don't bother for your everyday backup hard drive or similar, which is probably slower than your USB3 connection.

    There are also pro products for video and audio digitisation that can make use of Thunderbolt bandwidth.

    Also, Thunderbolt is an extension of the internal PCIe bus from which all the other interfaces are driven. So, an ethernet controller, extra USB port, hard drive controller etc. connected by Thunderbolt is a "first class" device largely equivalent to an internal device, without the speed overheads and possible incompatibilities of something driven via an 'intermediate' interface such as USB. USB ports on a Thunderbolt dock, for instance, can be "proper" extra USB ports with its own controller, rather than connected via a USB hub that 'shares' a single USB port between several devices (which can sometimes cause issues).

    Also, Thunderbolt can optionally use optical cables that are far, far longer than USB cables and less susceptible to electrical interference (nice if you want your 5k display & keyboard in the recording studio and the computer tucked away in the equipment room). That said, if you need to ask the price of optical TB cables, you can't afford them.

    No - that was true of the 12" MacBook, but the new MBPs have Thunderbolt 3. Its just that whereas Thunderbolt 1/2 used the same connectors as MiniDisplayPort (and still supported MiniDisplayPort devices), Thunderbolt 3 uses the same connectors as USB-C (and still supports the things that 'regular' USB-C connectors do).

    Odds are that the next version of the 12" Macbook will have Thunderbolt 3, too, since the next generation of Intel CPUs have a Thunderbolt controller built in.

    However - you're quite right that its only "power users" that will actually need Thunderbolt 3 and the addition of USB-C makes this even more so. If you're not a video/audio pro, a cheaper USB-C or USB 3.1 external drive will be more than sufficient. Even for multi-port docks, USB-C should do the job unless you want to run a 4k/5k display from the dock and really, really want that single-wire docking (what? plug two cables into my MacBook? Is this some kind of shampoo ad!?)
  7. MacBH928 thread starter macrumors 68030


    May 17, 2008
    Thanks for everyone's replies.

    So you are telling me there is nothing really that needs a 10/20/40 Gbps connection on its own other than a 4k/5k display?

    Its kind of funny, since this is about the only time I have heard of a technology being developed faster than the need for it. Usually a need rises, then 2-3 years later a solution comes by.
  8. bcave098 macrumors 6502a


    Sep 6, 2015
    Northern British Columbia
    There's a "need", but it's not one that 99.9% of users need.

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