You’re probably thinking of AVX, Advanced Vector Extensions. That’s a family of vector extensions that has been out for just over a decade (2011). This is about AMX, Advanced Matrix Extensions. AMX is, as the name implies, built around 2D INT8/BF16 matrices (not “1D” FP16/32/64 vectors). It’s not on silicon available to the public.

Also not to be be confused with VMX (AltiVec/Velocity Engine), which predates AVX by another decade or so.

To keep the record straight, we have: 1. AMX, 2. AVX, and 3. VMX.

There’s also Intel VMX, the Virtual Machine Extensions ;) Sometimes it’s referred to as VT-x.

Intel's AMX specifically hasn't yet shipped, but will be coming with their new Sapphire Rapids Xeon chips this year.

*Next year (potentially).

Sapphire rapids might well end up only shipping in Aurora and then being replaced immediately by it's successor.