Although Windows 7 and Vista can support capacities over 2.19 TB, a special PCI Express card will be bundled with the new 3 TB and 2.5 TB hard drives to overcome the hardware hurdle.
Tuesday Western Digital said that its 3 TB WD Caviar Green internal SATA HDD--slated as the world's largest thus far--is now available at select U.S. retailers and distributors. The drive will carry a $239 price tag and will be joined by an additional 2.5 TB model costing $189. Both will utilize 750 GB-per platter areal density and Advanced Format (AF) technology.
"WD Caviar Green drives are an eco-friendly storage solution with WD GreenPower Technology, which reduces power consumption by enabling lower operating temperatures for increased reliability and decreases acoustical noise for quiet operation," the company said Tuesday. "The WD Caviar Green 2.5 TB and 3 TB hard drives are designed for use as secondary external storage and next-generation PC storage in 64-bit-based systems."
The drawback to both capacities is that--on a hardware level--BIOS-based motherboards are limited, offering capacity support up to 2.19 TB. On the software front, 32-bit Windows operating systems prior to Vista share the same limitation, capable of handling 2.19 TB partitions or less thanks to their native support for the legacy Master Boot Record (MBR).
However MBR is expected to be replaced by the GUID Partition Table--which is already supported by Windows 7 and Vista--by the end of the year, and the BIOS will be replaced by the new Extensive Firmware Interface (EFI)--both of which will handle capacities over 2.19 TB. But that doesn't help current consumers wanting to take advantage of the expanded storage space.
To help overcome the current hardware and software limitations, WD is bundling the two drives with a PCI Express-based Advanced Host Controller Interface (AHCI)-compliant Host Bus Adapter (HBA) card which will enable the 32-bit and 64-bit versions of Windows Vista and Windows 7 to use a known driver with correct support for large capacity drives.
Unfortunately, even if installed on a machine with a EFI-embedded motherboard, Windows XP machines can't use either drive because the OS offers native support for MBR only.