A two-phase liquid immersion cooling system is described in which heat generating computer components cause a dielectric fluid in its liquid phase to vaporize. The dielectric vapor is then condensed back into a liquid phase and used to cool the computer components. The dielectric fluid may be stored in a bath portion of the cooling system. The cooling system may also include a shelf portion, which can hold at least one ballast block. The ballast block can provide for a deeper bath portion and flow of the dielectric fluid from a condenser.