I have an existing SATA 2 HDD in my system. I just bought a Samsung 200GB SERIAL ATA HD 7200/8MB/SATA-3G HDD which I assume is also SATA 2 based off the throughput speed. It is recognized in BIOS, but not in windows. Does anyone know what is going on? Does it matter if I mistakenly go a non SATA 2 HDD, w/ a MOBO that is designed for SATA 2. Even though BIOS sees it? I don't think it's the SATA controller drivers cause my other SATA HDD is detected just fine. I always check DM after installing my OS which I did a while back.