According to the one-page datasheet of a Foxconn M.2 M-key socket, maximum current per pin is 0.5 A (they're tiny, after all). Since M.2 M-key has a total of ni

According to the one-page datasheet of a Foxconn M.2 M-key socket, maximum current per pin is 0.5 A (they're tiny, after all). Since M.2 M-key has a total of nine pins carrying 3.3 V this would limit power to 15 W before any heat dissipation considerations plus connector derating because the toasty SSD is heating the connector up.