Oh, I see.
However, I have already given it up to use 32GB modules on macOS, because Apple should never (officially) support:
1) 32GB memory module;
2) macOS Catalina or later; and
3) NVIDIA GPU such as Titan X on Mojave or later macOS;
I plan to use Linux on MacPro5,1 with 192GB memory and Titan X (for Machine Learning).