137GB (128GB binary)
On many systems, the IDE/ATA interface uses a 28-bit addressing which cannot
recognize more than 137GB of storage. To overcome this capacity barrier, drives
higher than this capacity have adopted a 48-bit addressing system which can be supported in newer computer systems with updated controller chips, BIOS codes, and operating system
drivers (refer to your system documentation for more details). If your system does not support drives of this size, you have a few options.
Western Digital has included a controller card and drivers in many of our retail packaged drives that are greater than 137GB to address this operating system and BIOS limitation. During installation, drives larger than 137GB must be attached to the controller card and the drivers for your operating system must be loaded properly to avoid the risk of data loss. If you need a controller card, please visit our Online Store.