Western Digital 3TB Caviar Green Review

The Western Digital 3TB HDD is a member of the 5^th generation of Caviar Green product line.  This drive has a capacity of 3000GB or 3 Terabytes which is pretty amazing.   The drive has four platters each of which contains 750GB of data storage capacity. The drive has a 64MB cache and is on the SATA II (3 Gb/second) interface.  As is usual with SATA drives, Native Command Queuing is supported.

One issue that manufacturers have with the increasing HDD space is that motherboards are using Master Boot Records and the system BIOS.  Hard Disk Drives generally have a 512 byte sector size which if you work out the math gives a maximum size of 2.19TB or 2 to the 32^nd power of storage space.  This is a hard limit and is similar to what happens when you try to install 4GB of memory into a system running 32-bit Windows.

One way to break the 2.19TB barrier is to use a larger sector size and keep the number of addressable blocks the same. Using a sector size of 4096 bytes would result to have up to 17.59TB of addressable space, which is 2 to the 32^nd power times 4096. The issue with doing that is applications are designed for sector sizes of 512 bytes and issues would occur with compatibility. Western Digital has transitioned some of their drives to using 4096 byte sized sectors with them emulating the 512 byte sectors to maintain compatibility.

WD and other computer related companies have begun releasing solutions to replace the MBR and the BIOS. The BIOS will be replaced in newer systems by something called UEFI which stands for the Unified Extensible Firmware Interface.  The replacement for the MBR is called GUID Partition Tables or GPT.  This transitions the storage partitions to 64-bit partitions for up to 18 Exabytes of Logical Block Addressing.  The problem here is that there are incompabilities with system BIOS and 3^rd party storage drivers, meaning that another solution needed to be found.

With few UEFI motherboards on the market, Western and Seagate had a choice, either find an interim solution to bridge the gap between the lacks of UEFI motherboards or wait until the boards reach enough saturation for them to be widely used.  Western Digital is bundling a HighPoint RocketRAID 620 card with their HDD to allow the users to address all 3TB of HDD space on the drive without it having a UEFTI to address 3TB instead of 2.19TB.  The card requires a free PCI Express x1 slot and acts as a Host Bus Adapter by enabling boot support for 64-bit operating systems such as Apple’s OSX 10.5, Windows 7 64-bit or Linux.  Here’s a chart with the  The card requires a free PCI Express x1 slot and acts as a Host Bus Adapter by enabling boot support for 64-bit operating systems such as Apple’s OSX 10.5, Windows 7 64-bit or Linux.  Here’s a chart with the supported modes of different Operating Systems as Boot, Secondary, USB External Storage and whether the drives require a HBA: