That's IDE. Don't get a 5400RPM HDD for a desktop. That might be fine for notebooks, but heat and noise don't really matter in a desktop. Also make sure that the HDD you get has at least an 8MB cache, but preferably 16MB. Seagate is awesome. I have two of their 120GB SATA150 drives that have been working flawlessly (knock on wood) for two years now.