Answer series recovery mechanism

An improved response resequencing technique for use in a South Bridge element or I / O hub or similar device is provided. Non-posted read requests are received from at least a requesting entity and sent upstream commands based on the non-posted read requests. Each of the upstream commands is uniquely identified by a command mark. If response data are received in response to previously transmitted commands, responses are transmitted to the at least one requesting unit on the basis of the response data. The transmission of the responses includes reordering the received response data by accessing a buffer of the South Bridge device. The buffer stores the received response data and has a plurality of buffer elements, the one of the instruction tags are uniquely assigned to each.