Seagate has entered the notebook hard drive market with volume shipments of its new Momentus product. As the only independent maker of notebook hard drives, leading notebook computer makers have welcomed Seagate's entry into the fastest growing segment of the computer market. Momentus is the industry's first notebook hard drive to combine a high-performance 5,400-rpm spindle speed with the low battery-consumption of a traditional 4200-rpm notebook hard drive, so customers no longer have to choose between performance and mobility. Seagate's patented SoftSonic fluid dynamic motor and new QuietStep ramp load technology make Momentus one of the quietest, most rugged notebook hard drives available. Momentus delivers 5400-rpm spin speed, optional 8-Mbyte cache, and low battery consumption that's competitive with 4200-rpm hard drives thanks to careful optimization of power management in the drive's electronics. Tests show that Momentus is 47 percent faster at opening a 12-Mbyte Excel file, 30 percent faster at copying a 170-Mbyte folder, and 47 percent faster at shutting down Windows XP than today's standard 4200-rpm notebook drives. With the 8-Mbyte cache option, the drive performs up to an additional 15 percent faster. Seagate is well known for its quiet and rugged hard drives, and has made Momentus whisper-quiet by using proven Seagate SoftSonic FDB motors and the innovative QuietStep ramp load technology. QuietStep parks the heads safely off the disc during standby, but reduces the clicking sound typically made by other notebook hard drives when loading and unloading its heads to the ramp. Seagate's rugged design gives Momentus a 225-G operational shock tolerance, among the best in the industry. Momentus offers popular capacities of 20 and 40 Gbytes on a robust one-platter design, and is shipping to OEM customers now.