This rack (1) houses rackable electronic gear modules (2, 3) and has cooling by natural convection thanks to ventilation orifices (20, 21) provided in its bottom (10) and top (11) walls and forced air cooling thanks to internal air distribution ramps (30) fed with air under pressure through the intermediary of a distribution box (31) connected to a forced air circulation duct (37). The use of internal distribution ramps for the forced air makes it possible to produce a pulsed air circulation providing only a slight obstacle to the air circulation obtained by natural convection. Compared to usual configurations, this makes it possible to lower the operating temperature reached by the equipment in the event of loss of the forced ventilation.