A pyramidal case for receiving a computer having a mother-board equipped with a CPU, said pyramidal case comprising a squared base, which has a support on a box, with a rectangular rear section and a trapezoidal front section, - wherein the motherboard (o) is provided with its lower part above a slot-in reader above the base of the case, with the CPU carrying a finned heat sink (q) being positioned at the upper side of the mother-board, and - wherein the following air flow arrangement within the pyramidal case is provided: • fresh air is sucked in from the outside by an impeller (c) provided in the base of the pyramidal case at one side of the mother-board, • an air flow deflector (e) is provided at said one side of the mother-board for dividing the sucked-in air into an air flow crossing the space between the lower side of the mother-board and the slot-in reader at the base of the case and an air flow directed to the upper side of the mother-board, • a further impeller (i) being provided above the CPU heat sink (q) within a wall defined by two further air flow deflectors (h,l) separating the pyramidal case into a lower and an upper part wherein causing a depression going through the heat sink fins for cooling the CPU and drawing in the air flows at the lower and upper sides of the mother-board, a warm air flow being directed by the further impeller (i) to the apex and expulsed through expulsion grids placed at the apex to the outside of the case. - wherein the motherboard (o) is provided with its lower part above a slot-in reader above the base of the case, with the CPU carrying a finned heat sink (q) being positioned at the upper side of the mother-board, and - wherein the following air flow arrangement within the pyramidal case is provided: • fresh air is sucked in from the outside by an impeller (c) provided in the base of the pyramidal case at one side of the mother-board, • an air flow deflector (e) is provided at said one side of the mother-board for dividing the sucked-in air into an air flow crossing the space between the lower side of the mother-board and the slot-in reader at the base of the case and an air flow directed to the upper side of the mother-board, • a further impeller (i) being provided above the CPU heat sink (q) within a wall defined by two further air flow deflectors (h,l) separating the pyramidal case into a lower and an upper part wherein causing a depression going through the heat sink fins for cooling the CPU and drawing in the air flows at the lower and upper sides of the mother-board, a warm air flow being directed by the further impeller (i) to the apex and expulsed through expulsion grids placed at the apex to the outside of the case. • fresh air is sucked in from the outside by an impeller (c) provided in the base of the pyramidal case at one side of the mother-board, • an air flow deflector (e) is provided at said one side of the mother-board for dividing the sucked-in air into an air flow crossing the space between the lower side of the mother-board and the slot-in reader at the base of the case and an air flow directed to the upper side of the mother-board, • a further impeller (i) being provided above the CPU heat sink (q) within a wall defined by two further air flow deflectors (h,l) separating the pyramidal case into a lower and an upper part wherein causing a depression going through the heat sink fins for cooling the CPU and drawing in the air flows at the lower and upper sides of the mother-board, a warm air flow being directed by the further impeller (i) to the apex and expulsed through expulsion grids placed at the apex to the outside of the case.