EK Water Blocks has already released a water block for the GeForce RTX 4080. There is a full-cover water block that can cool the GPU core, memory, and power supply circuit all at once. 

The base plate has an 11-mm-thick copper cold plate. The cooling performance has also been improved by combining the "Open Split-Flow cooling engine design" and the "Asymmetric Shape of the Jet Insert," which stops the coolant liquid from flowing backwards and keeps the flow rate the same even with a low-output pump. The "EK-Quantum Vector2 FE RTX 4080 D-RGB – Nickel + Plexi" model has a top cover made of clear acrylic, and the "EK-Quantum Vector2 FE RTX 4080 D-RGB, Nickel" model has a top cover made of black acetal.

Both have a lighting function that uses addressable RGB LEDs and come with a back plate and a 1-slot thick bracket.

GeForce RTX 4080 FE water block already available from EKWB