Nvidia GeForce RTX 4090 and 5090 prototypes exposed — development and testing cards had four 16-pin power connectors
by from Latest from Tom's Hardware on (#6V7C4)
A leaker managed to get ahold of some of Nvidia's latest-generation development/bring-up boards. The prototype hardware features extra power interfaces, test points, debugging interfaces, and plenty of jumpers scattered around the PCB.