A computer housing (41) for free-standing use includes a computer (10) with slots for the insertion of extension cards, and further at least one card carrier (20) for carrying extension cards (51). The card carrier (20) includes a carrier connector (47) whereby the card carrier (20) is connectable, by inserting the card carrier (20) in the computer housing (41), via the carrier connector (47), with a communication connector (49) of the computer (10), at least one adapter connector (48) into which an extension card (51) is pluggable, and wherein the card carrier (20) includes a communication connection between the carrier connector (47) and the at least one adapter connector (48).