Seagate Momentus 5400.3 40GB, 40 GB, 5400 RPM, 8 MB, 2.5", Serial ATA Seagate Momentus 5400.3 40GB. HDD capacity: 40 GB, HDD speed: 5400 RPM, Storage drive buffer size: 8 MB, HDD size: 2.5", Interface: Serial ATA