The invention relates to an X-ray tube whose cathode arrangement includes a flat electron emitter that is provided with openings. The at least one plug element has at least one support element that extends from the plug element in the space between the bottom housing part and the printed circuit board in such a way that a section of it rests against the side of the bottom housing part facing the printed circuit board. Operating the cooling fan in the normal load operation mode may mean reducing a cooling fan operation frequency and decreasing a cooling fan operation percentage over a predetermined coolant temperature range.