The Western Digital WD400BB is an internal hard drive with decent storage capacity that allows you to store all your files and data. The IDE Ultra ATA100 interface of this WD internal HDD provides you quick and easy connectivity. The 7200 rpm rotational speed of this WD hard drive offers an efficient transfer performance. The Western Digital WD400BB HDD has 8.9 ms of average seek time that helps you locate your files and folders quickly. Process your files and data at a faster rate with the 2 MB cache of this WD internal HDD. The Quiet Drive technology of this WD hard drive offers silent performance, making it ideal for domestic use.