This read-only integer counts transmit packets from this PC that were aborted due to excessive collisions. An admin treats a nonzero excess-collision count as evidence of severe contention specific to this PC's connection, more serious than the routine single or multiple collision counts. For example, a PC showing rising pcXcessColls alongside otherwise normal collision counts on peer machines would point the admin toward a problem specific to that PC's cable or port rather than general segment congestion.