Transaction exchanges are controlled between two integrated circuits in a system having the integrated circuits (ICs), a power supply supplying power to a link between the ICs, thereby enabling transaction exchanges between both ICs and a controller controlling the ICs and the power supply. This involves receiving an order at the controller, wherein the order requires the link to be closed. An instruction is sent from the controller to each of the two ICs, wherein the instruction causes each of the ICs to stop initiating new transaction requests. For each one of the ICs, in response to detecting that the one of the two ICs has stopped initiating new transactions, it is detected when all pending transactions initiated by the one of the two ICs have been executed. The link is closed in response to detecting that all pending transactions of both of the two ICs have been executed.