An improvement in a fetch overlap feature for a data processing system results from providing multiple interfaces between the system data processor and the system memory. The memory is divided into a plurality of independent units each having its own interface. The data processor can retrieve more than one word from the memory system at the same time without incurring contention between memory access orders. The data processor is thereby enabled to begin to fetch its next instruction even if its current instruction orders the data processor to retrieve an operand.