I cannot believe I’m saying that, but: for apple that’s rather cheap. Threadripper boxes with that amount of memory do not come a lot cheaper. Considering what apples pricing when it comes to memory in other devices, 4K for the 96GB to 512GB upgrade is a bargain.
It's not that much cheaper that with earlier comparable models. Apple memory prices have been $25/GB for the base and Pro chips and $12.5/GB for the Max and Ultra chips. With the new Studios, we get $12.5/GB until 128 GB and $9.375/GB beyond that.
If you configure a Threadripper workstation at Puget Systems, memory price seems to be ~$6/GB. Except if you use 128 GB modules, which are almost $10/GB. You can get 768 GB for a Threadripper Pro cheaper than 512 GB for a Threadripper, but the base cost of a Pro system is much higher.
