An automatic wafer probing system is disclosed as being located inside an environmental box filled with a positive pressure dry inert gas. The wafer to be probed is mounted on a Thermochuck that has a high thermal contact with the wafer. The chuck can be precisely heated or cooled over the temperature range of -60.degree. C. to +200.degree. C. An atmosphere of dry N.sub.2 gas allows sub 0.degree. C. wafer probing without condensation on the wafer. The box is constructed of metal so as to shield any electromagnetic interferance that could possibly disrupt the testing procedure. A probe card produces probe contact with the chip circuits on the wafer and data taken at desired temperatures. The box includes a window that is in registry with the probe contacts and an externally mounted microscope looks through the window at the probe region. The wafer and window are rendered moisture free by dry N.sub.2 gas. The wafer probing action and the probe testing is under the control of a desktop computer.