Sata will give u most bang for your buk, its faster then ide, but the worst thing u could do is buy a sata hd then find out it wont work on your mobo. Make sure u do ur homework b for u make your decision. Or ask sum one who knows wat there doing. But usually if you buy a stock computer like a HP or sumthink from the 2000's to 2004 u need a ide hdd, but if u have a custom build computer from that time period u could usually have a sata hdd installed tho you could also check the manual that came with your mobo. But most computers 2004 onwards should support sata and sata2.