At least according to wikipedia each pin is rated up to 0.5A with I think nine 3.3v pins so technically just around ~15W peak Technically that's what U.2 (2.5

At least according to wikipedia each pin is rated up to 0.5A with I think nine 3.3v pins so technically just around ~15W peak Technically that's what U.2 (2.5 inch form factor for SSDs) would be for. They get 5V/12V and thicker connector, I severely doubt M.2 could swing 25W as it only has 3.3V on it