Western Digital launches 3TB Caviar Green hard drive

Matthew DeCarlo

Posts: 5,271   +103

Two weeks after announcing its 3TB My Book Essential external storage drive, Western Digital has launched the first bootable 3TB desktop HDD. The WD30EZRSDTL is the latest in Western Digital's Caviar Green line and features four 750GB platters pancaked into a standard 3.5-inch casing. It spins 5400RPM, uses SATA 3Gb/s to interface with the host machine, and utilizes Advanced Format (AF), which uses 4KB sectors instead of the typical 512-byte sectors.

Hard drive manufacturers have been slow to ship a 3TB product, at least partly because it's a pain to create a bootable operating system partition on a volume larger than 2.19TB. The Master Boot Record (MBR), which tells your computer the location of each sector, can only address 2^32 (4,294,967,296) sectors, which amounts to 2.19TB when using the typical 512-byte sector format. Things get hairy beyond that capacity.

To create a boot volume larger than 2.19TB, you need a 64-bit OS, support for GPT partitions (which can address 2^64 sectors), and a motherboard with UEFI instead of the standard BIOS. Since most current systems don't yet support UEFI standards, WD has included a known-compatible AHCI-compliant PCI-Express Host Bus Adapter (HBA) card as a workaround. HBA adapter or not, Windows XP 32-bit and 64-bit users are out of luck.

Nonetheless, it's obvious that the 3TB Green is mostly intended to be used for secondary bulk storage, and as Storage Review notes, the rules are slightly different in a non-boot scenario. The average PC user doesn't need a 3TB boot volume anyway and would be better served by something smaller and quicker. Western Digital has priced the 3TB WD30EZRSDTL at $239 (HBA card included), while a 2.5TB iteration (WD25EZRSDTL) is $189.

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Posts: 872   +151
Use an SSD for your OS and then point your User files to the other drive. I have a 4tb partition using four 1tb wd black w/ 64mb cache and it's extremely fast. 330MB/s burst, 220MB/s sustained, but the random seek is 14ms.


Posts: 526   +15
I assume with speeds like that, you're using RAID 0? If one of those fails, you loose everything. I believe that RAID 0 is never worth it unless it's all backed up

Per Hansson

Posts: 1,976   +233
Staff member
Is it possible to use this as a boot drive if you create two partitions and make the boot partition smaller than 2TB on a normal BIOS mainboard that does not support EFI?