The prototype card is longer than the Radeon 6900, but it has the same power connector arrangement as the RDNA2 GPU, which is a twin 8-pin connector.
Because there is no capacity for more power hookups, this might be either the Radeon 7900 XT or the top 7900 XTX, which are likely to share the same triple-fan architecture. This prototype is not a finished product; the backplate, which is featured on all high-end RDNA2 reference models, is plainly missing. Furthermore, do not be concerned about the red PCB; it will undoubtedly be replaced with a black one.
AMD is now likely to reveal its Radeon 7900 series on Thursday, with a product availability in early December rumoured. At least two cards, the 7900XT and 7900XTX, based on the Navi 31 GPU with RDNA3 architecture and a novel chiplet design, will be revealed.