A test assembly for testing a device under test includes a probe card assembly and a cap secured to the probe card assembly. The probe card assembly includes a probe tile having a plurality of openings. The probe tile includes a plurality of probe wires including a probe needle portion and a probe tip portion. A seal is disposed on a surface of the probe tile and forms an outer perimeter of a pressurized area. The probe tile includes an insulation layer formed within the pressurized area that is configured to separate the probe needle portion from the device under test. The insulation layer includes an aperture through which the probe tip portion extends to contact the device under test. The cap includes a fluid inlet and a fluid return outlet that are in fluid communication with the plurality of openings of the probe tile.