I have used an ATX PSU to create a power bench tester for testing automotive headlights. HID in particular which draw around 8-10amps on startup. I have noticed that whenever I start the bench with such a draw, the USB ports on my PC, connected to the same wall socket, disconnect and reconnect immediately. When tested with a standard 55W halogen bulb, the problem doesn't occur.
I don't recall doing that before therefore what could've gone wrong in my circuit to cause perhaps a jump in amps or what can I do to prevent troubles to my PC's USB devices?
I have used a 12V wire connected to a binding post by squishing the wire between the two nuts - afterward a binding connector which is crimped to a wire which has a female connector to which the HID bulb connects to. I have jumped the green/ground wires in order to start the PSU.
Everything is properly insulated with electrical tape.