A USB (universal serial bus) controllable power supply and method for supplying power to a circuit board device under test (DUT) via a controllable power supply. The power supply employs a USB interface to communicate with external devices, such as a host computer. In response to power supply control commands from the host computer, the controllable power supply provides various power outputs at various external connectors, including main power, ATX12V power, and peripheral power to be used for peripheral devices corresponding to a DUT test apparatus. The controllable power supply also provides a built-in short circuit check function, and monitors the voltage levels of its power outputs to ensure they are within predefined limits. The power supply also supports emergency shutdown operations, and provides an EOS (emergency overstress) function. In one embodiment, the power supply includes an integrated USB hub.