MojoKid writes "Today, Western Digital announced the world's highest density hard drive, as they reach the 3TB mark with their newest, 5th generation Caviar Green product. The Caviar Green 3TB serves up a super-sized combination of reduced power consumption, lower operating temperature, and a quieter operation. Unfortunately, if you're still using Windows XP, don't expect your system to make full use of any 3TB drive (yet). The problem is that older operating systems, in combination with a legacy BIOS and master boot record (MBR) partition table scheme, face a barrier at 2.19TB. Existing motherboards utilizing BIOS (non-UEFI), GPT ready operating systems like Windows 7 64-bit, and appropriate storage class drivers, can address the entire capacity of hard drives larger than 2.19TB. Another issue is that a number of host bus adapter (HBA) and chipset vendors don't offer driver support for these types of drives. To provide a solution for this compatibility issue, Western Digital bundles an HBA with the Caviar Green 3TB drive that allows the operating system to use a known driver to correctly support extra large capacity drives. This solution is reportedly just temporary until the rest of the industry catches up."