A system comprising: a blade enclosure (101, 402); a midplane (120, 410, 710) within the blade enclosure (101, 402), the midplane (120, 410, 710) supporting at least a first sleeve connector, said first sleeve connector having a first side and a second side; a server blade (102, 202, 302, 702) installed in the front of the blade enclosure (101, 402), the server blade (102, 202, 302, 702) comprising a first component (106, 306a, 306b) and a second component (108, 308a), one or more enclosure fans in the rear of the blade enclosure, configured to provide a primary air flow path which draws air into the server blade (102, 202, 302, 702) from the front of the blade enclosure (101, 402) and exhausts air to the rear of the blade enclosure (101, 402); the server blade (102, 202, 302, 702) further comprising an air duct (110, 210, 310, 724) within which the second component (108, 308a) is arranged, the air duct (110, 210, 310, 724) being coupled to the first side of the first sleeve connector; and a cooling module (150, 420, 502, 602, 762) located in the rear of the blade enclosure, the cooling module (150, 420, 502, 602, 762) comprising an air manifold (152, 422, 514, 614), the air manifold (152, 422, 514, 614) coupled to the second side of the first sleeve connector to deliver cool air to the air duct (110, 210, 310, 724) of the server blade (102, 202, 302, 702), the cooling module drawing cool air into the blade enclosure from the front of the enclosure through enclosure side-channels, wherein the air delivered to the air duct (110, 210, 310, 724) of the server blade (102, 202, 302, 702) flows, in at least a portion of the air duct (110, 210, 310, 724), in a different direction to the primary air flow path across the server blade (102, 202, 302, 702). a blade enclosure (101, 402); a midplane (120, 410, 710) within the blade enclosure (101, 402), the midplane (120, 410, 710) supporting at least a first sleeve connector, said first sleeve connector having a first side and a second side; a server blade (102, 202, 302, 702) installed in the front of the blade enclosure (101, 402), the server blade (102, 202, 302, 702) comprising a first component (106, 306a, 306b) and a second component (108, 308a), one or more enclosure fans in the rear of the blade enclosure, configured to provide a primary air flow path which draws air into the server blade (102, 202, 302, 702) from the front of the blade enclosure (101, 402) and exhausts air to the rear of the blade enclosure (101, 402); the server blade (102, 202, 302, 702) further comprising an air duct (110, 210, 310, 724) within which the second component (108, 308a) is arranged, the air duct (110, 210, 310, 724) being coupled to the first side of the first sleeve connector; and a cooling module (150, 420, 502, 602, 762) located in the rear of the blade enclosure, the cooling module (150, 420, 502, 602, 762) comprising an air manifold (152, 422, 514, 614), the air manifold (152, 422, 514, 614) coupled to the second side of the first sleeve connector to deliver cool air to the air duct (110, 210, 310, 724) of the server blade (102, 202, 302, 702), the cooling module drawing cool air into the blade enclosure from the front of the enclosure through enclosure side-channels, wherein the air delivered to the air duct (110, 210, 310, 724) of the server blade (102, 202, 302, 702) flows, in at least a portion of the air duct (110, 210, 310, 724), in a different direction to the primary air flow path across the server blade (102, 202, 302, 702).