Western Digital HDD WD2500AAKX 250GB SATA 7200rpm 16MB Cache 3.5inch Hard Drive WD Caviar Blue hard drives have a multitude of features including third generation SATA interface with 6 GB/s transfer rate. Plus rock solid performance and ultra-cool and quiet operation. WhisperDrive technology minimizes noise to levels near the threshold of human hearing. SoftSeek technology streamlines read/write seeking algorithms, resulting in more efficient operation.