ASRock P4 Combo motherboard is a wise choice for upgrade-demanded and budget-concerned users. Users can use legacy CPU (Socket 478) for the moment with less cost and still enjoy the possibility for the future upgrade to LGA775 CPU. This motherboard contains both Socket478 and LGA775 sockets. User can freely enjoy up-to-date CPU technology in PC system for years without changing the motherboard. Users can choose Socket 478 CPU today and look forward to the future upgrade of LGA775 CPU when the LGA775 CPU price drops. The combo sockets are well designed and tested to achieve both Socket 478 and LGA775 standards.