Apple LED Cinema Thunderbolt Display

There is no such thing as an "Apple LED Cinema Thunderbolt Display."

There is an Apple LED Cinema Display (27-inch), model A1316 – and an Apple Thunderbolt Display (27-inch), model A1407. It is critical to know which of these two you have. Their cables might both use Mini DisplayPort connectors, but they expect different types of signals, which in turn dictates the choice of adapter.

The LED Cinema Display has a hydra cable with three heads: Mini DisplayPort, USB, and MagSafe. To connect it to a M2 Mac mini, you would need a USB-C (male) to Mini DisplayPort (female) adapter. You would not want to use an Apple Thunderbolt 3-to-2 adapter, as that adapter just translates Thunderbolt and does not know how to present a plain DisplayPort signal on its Thunderbolt 2 side.

If you have the LED Cinema Display, you will also want to plug the USB head of the hydra cable into your Mini or into a hub/dock connected to your Mini. If you don't, I don't think there will be any way to control brightness.

The Thunderbolt Display has a hydra cable with two heads: Thunderbolt (old-style Mini DisplayPort connector) and MagSafe. To connect it to a M2 Mac mini, you would need an Apple Thunderbolt 3-to-2 adapter. You could not use a USB-C to Mini DisplayPort adapter because such an adapter would not provide a Thunderbolt signal.

Another way to tell the displays apart is that the Thunderbolt Display has FireWire 800 and Ethernet hub ports. The LED Cinema Display doesn't. (Both have USB 2.0 hub ports, so that isn't a distinguishing feature.)

Note that the "hydra cables" on the old Thunderbolt Displays sometimes go bad – or are flaky enough that newer versions of macOS blank out the display upon detecting transmission errors.

A workaround for that is to get a Thunderbolt 1/2 cable and run it from the TB2 side of the TB3-to-2 adapter to the TB daisy-chaining port on the Thunderbolt Display, bypassing the flaky or defective "hydra cable."