Screenshots of the heatsink of the GeForce RTX 4090 have reported surfaced over at the Chiphell forums. Going by these shots, it would seem that NVIDIA has decided to retain the heatsink design of its Founders’ Edition cards. The fin design and overall build look exactly like that of the RTX 3090 Ti. In fact, I wouldn’t be surprised if that’s what it is. Going by these pictures, the only difference is with respect to the size and fin density.
The purported RTX 4090 FE heatsink is notably larger with an extended aluminum plate to encompass the VRAM chips in addition to the GPU core. The fins on the side also seem wider and denser but other than that there’s not much of a difference.
Be sure to remember that this is likely one of the many designs presented to NVIDIA by its partners and may or may not be the shortlisted one.