Apple Thunderbolt Cable 2MMD861ZM/A

Apple Thunderbolt Cable 2MMD861ZM/A

The Apple Thunderbolt Cable 2MMD861ZM/A is Apple’s own Thunderbolt cable in the 2.0 metre length; the “2M” in the listed name is the cable length, and MD861ZM/A is Apple’s model number. It connects Thunderbolt-equipped Mac computers and peripherals from the Thunderbolt 1 and Thunderbolt 2 generation, the machines that carry the Mini DisplayPort-shaped Thunderbolt port. One cable carries both PCI Express data and DisplayPort video, which is why a single lead can serve external storage, a display, or even a second Mac.

Key Features

• Two independent 10 Gbps channels: Apple specifies Thunderbolt with two independent data channels of 10 Gbps each, one reason transfers feel so much faster than the USB and FireWire connections it replaced.
• Up to 20 Gbps on Thunderbolt 2: On Thunderbolt 2 equipment, the two channels bond into a single channel of up to 20 Gbps for the fastest compatible drives and arrays.
• Full 2.0 metre length: The longer of Apple’s Thunderbolt cable lengths, giving freedom to place storage, a display or a second Mac where the desk layout actually needs it.
• Data and video on one cable: Thunderbolt carries PCI Express for data and DisplayPort for video together, so peripherals and displays share one connection standard.
• Daisy-chaining: Thunderbolt supports connecting up to six devices in a chain from a single computer port, in sequence, rather than one port per device.
• Target Disk Mode: Apple documents this cable for Target Disk Mode between two Mac computers that support Thunderbolt, mounting one Mac as a drive on the other.
• iMac as a display: Apple also documents using the cable to use a compatible iMac as a display for a Thunderbolt-equipped MacBook Pro.

Two Protocols, One Connection

Thunderbolt was designed by Intel in collaboration with Apple to merge two jobs that previously needed separate cables. PCI Express handles data, which is why Thunderbolt storage performs like internally connected storage rather than like a slow external bus, and DisplayPort handles video, which is why the same port can drive a display. The Apple Thunderbolt Cable is the genuine interconnect for that system: it is the cable Apple specifies for connecting Thunderbolt peripherals to an iMac, Mac mini, MacBook Pro or MacBook Air, and its 2.0 metre length is the maximum Apple recommends for a copper Thunderbolt cable to hold full performance.

The connector deserves one clear note. Thunderbolt 1 and 2 use the Mini DisplayPort plug shape, so this cable looks like a display cable and fits the same socket, but it is a true Thunderbolt cable carrying data as well as video. It is not a USB-C cable and does not fit USB-C or Thunderbolt 3, 4 or 5 ports directly; those newer machines work with this generation of equipment through Apple’s own adapter route, not by forcing a connection.

Target Disk Mode and Mac-to-Mac Work

Some of the most useful jobs for this cable involve two Macs. In Target Disk Mode, one Thunderbolt Mac starts up as an external drive for the other, which makes it the fastest wired route for migrating a system to a new machine, rescuing files from a Mac that will not boot normally, or moving a large library without a network in between. The same cable supports Target Display Mode on compatible iMac models, letting the iMac serve as an external monitor for a MacBook Pro. Both uses depend on a genuine Thunderbolt connection; a video-only Mini DisplayPort lead cannot substitute, because it carries no Thunderbolt data.

Daisy-Chaining and Everyday Setups

Because Thunderbolt devices pass the connection through, up to six devices can sit in a single chain: storage first, further peripherals behind it, and typically a display at the end. For the studios and offices still running Thunderbolt 1 and 2 hardware, including external RAID enclosures, Thunderbolt audio interfaces and Apple Thunderbolt Displays, that keeps a desk working from one computer port with short, orderly cable runs. The 2.0 metre reach of the MD861ZM/A helps here, bridging the gap between a machine under a desk and peripherals or a display on top of it without tension on the plugs.

The Apple Thunderbolt Cable 2MMD861ZM/A is the correct, manufacturer-made lead for the Thunderbolt 1 and 2 generation of Mac equipment: 2.0 metres long, two 10 Gbps channels, up to 20 Gbps with Thunderbolt 2, and documented by Apple for peripheral connection, Target Disk Mode and iMac display use.