To meet the upcoming high power density demand with high energy saving, Wiwynn developed an immersion cooling tank solution with 48V DC power delivery. One hundred OCP Tioga Pass server boards are immersed in a tank with 1.2m x 1.2m footprint. Two-phase immersion cooling technology is employed due to the high power density capacity and low Power Usage Efficiency (PUE) with warm water cooling. For easy service and high density design, each two boards are face-to-face compacted in a cartridge with one-hand released handle which is installed in the tank vertically to connect 48 V power bus bar. Sloped top cover design with 1.2 meter tank height design allows the front side service for the cartridge on rear side of the tank. Proprietary condenser system and water flow rate control are integrated in the tank management system to minimize vapor leakage during maintenance.