$NVDA Rubin Ultra is rumored to have shifted from a 4-die design to a 2-die design, which has raised concerns that testing complexity, carrier board requirements, and some supply chain demand could end up lower than previously expected

The market initially feared this would also hurt the cooling opportunity, but analysts argue that view is too simplistic. They say the GPU would still rely on full-plate liquid cooling, so the overall cooling architecture does not change in a meaningful way just because the die count is lower
There is also uncertainty around the technical roadmap, with analysts saying Rubin Ultra may drop the MCL solution for now and focus on MCCP instead, which suggests that product validation and design details are still evolving
Despite the design rumors, institutional investors still favor the leading cooling supplier because they expect stronger-than-expected gross margin, continued demand from existing GB and VR liquid cooling plates, and additional upside from future rack-level architectures that use more liquid-cooled components across GPUs, CPUs, DRAM, and networking