Western Digital Caviar Black WD7501AAES 750GB 3.5" 7200 RPM 32MB Cache SATA 3GB/s Internal HDD Hard Disk Drive WD7501AAES-75W7A0. WD Model Number: WD7501AAESWD Part Number: WD7501AAES-75W7A0Dell Part Number: 0T7NX 00T7NX TH-00T7NX Specifications: Disk Family Caviar BlackForm Factor 3.5" Capacity 750 GB (750 x 1 000 000 000 bytes) Number Of Disks 2 Number Of Heads 3Rotational Speed 7200 RPM Rotation Time 8.33 ms Average Rotational Latency 4.17 ms Disk Interface Serial-ATA/300 Buffer-Host Max. Rate 300 MB/seconds Buffer Size 32768 KB Drive Ready Time (typical) 11 seconds Average Seek Time 8.9 ms