The new drive MK1237GSX features Perpendicular Magnetic Recording technology (PMR) which allows for maximum data capacity on small form factor. The drive's 5,400 rpm motor speed improves system-level performance by as much as 12 percent when compared to 4,200 rpm. With a capacity of 120GB, this Toshiba HDD provides mobile PC manufacturers with the ideal hard disk drive to produce faster performing and application enriched notebooks.