Dear Customer,
Since Z790 motherboards are ATX, they are compatible with the Titan x 1.2v.
However, the bent tubing might not fit with the Z790 motherboards.
We have the CPU water blcok BP-CPUMPRO-DRGB which fits for LGA 1700.
https://shop.bitspower.com/index.php?route=product/product&product_id=8193&search=1700
When you change the CPU water block and motherboard,
You need to change the bent tubing or some fittings.
These depend on the actual distance between the CPU and the distro plate.