I've recently built a TR-based DL/ML workstation and bought 128GB ECC 2,667MHz UDIMMs for ~$1600, roughly the same price as 2990WX, but would have vastly preferred to get 256GB instead. Unfortunately, only Samsung is now sampling 32GB ECC DDR4 UDIMMs - I haven't seen them anywhere yet, and I expect the price is going to be insanely high :-(