Thunderbolt 2 backwards compatibility of M2 minis

[imrazor]

I've been thinking about getting a mac mini to complement my M1 MBA. Said Air works fine (via adapter) with my old-ish TB2 LG 34UM95P. But since the newer models are advertising Thunderbolt 4, I'm concerned about backwards compatibility. I know my work laptop with TB4 does not work with the older monitor, though I can use DP or HDMI.

If I can use DP or HDMI, why do I care? Thunderbolt gives me a 3rd input to work with, and I attach a lot of different sources to this particular monitor. So I'd like to keep that port viable...

 

[chrfr]

I've been thinking about getting a mac mini to complement my M1 MBA. Said Air works fine (via adapter) with my old-ish TB2 LG 34UM95P. But since the newer models are advertising Thunderbolt 4, I'm concerned about backwards compatibility. I know my work laptop with TB4 does not work with the older monitor, though I can use DP or HDMI.

If I can use DP or HDMI, why do I care? Thunderbolt gives me a 3rd input to work with, and I attach a lot of different sources to this particular monitor. So I'd like to keep that port viable...

Thunderbolt is backwards compatible; you just need this adapter: https://www.apple.com/shop/product/MMEL2AM/A/thunderbolt-3-usb-c-to-thunderbolt-2-adapter.
If it works with your M1 Mac, it'll work fine with an M2/M2 Pro Mac as well.

 

[imrazor]

@chrfr While you're possibly correct about the new M2 working, TB4 is *not* backwards compatible with TB2. I have two PC laptops, one with TB3 and a work laptop with TB4. The one with TB3 works fine (via adapter) with the TB2 monitor, while the TB4 model absolutely refuses to work.

From the horse's mouth:

Thunderbolt FAQ

Are Thunderbolt™ 4 PCs backwards compatible with Thunderbolt™, Thunderbolt™ 2, or Thunderbolt 3 based accessories?Accessories built to Thunderbolt and Thunderbolt 2 specifications are not supported by Thunderbolt 4 PCs.
Accessories built to the Thunderbolt 3 specification are fully supported by Thunderbolt 4 PCs.

These are anecdotal user reports, but many TB4 users here are saying they can't connect TB2 devices either:

https://www.reddit.com/r/Thunderbolt/comments/uwok43

 

[chrfr]

@chrfr While you're possibly correct about the new M2 working, TB4 is *not* backwards compatible with TB2. I have two PC laptops, one with TB3 and a work laptop with TB4. The one with TB3 works fine (via adapter) with the TB2 monitor, while the TB4 model absolutely refuses to work.

From the horse's mouth:

Thunderbolt FAQ

The situation is different with Apple computers- that adapter works fine with many devices on M2 based Macs, and is listed as compatible with the 2023 Mac minis, as well as other Macs with Thunderbolt 4.
See also this Apple document that calls out use of a Thunderbolt 2 display specifically: https://support.apple.com/guide/mac-mini/connect-a-display-apd8e4fbbb97/mac

 

[joevt]

@chrfr While you're possibly correct about the new M2 working, TB4 is *not* backwards compatible with TB2. I have two PC laptops, one with TB3 and a work laptop with TB4. The one with TB3 works fine (via adapter) with the TB2 monitor, while the TB4 model absolutely refuses to work.

From the horse's mouth:

Thunderbolt FAQ

These are anecdotal user reports, but many TB4 users here are saying they can't connect TB2 devices either:

Thunderbolt 4 PC's did support TB2/TB1 but a firmware update removed the support. #2,902