More than just your ordinary laptop IDE hard drive, this new series, dubbed âMomentusâ, can come with an 8MB cache and speeds up to 5,400RPM, much faster than the industry standard of 4,200RPM for 2.5â drives. With such a large capacity in a small area, the 5400RPM 120GB model is able to outperform a similar offering from Hitachi, the 7k60, which is one of the very few 7200RPM laptop hard drives available. Aside from 120GB on that small of a disc being impressive in and of itself, a larger disc on the same size and number of platters means denser data, and thus faster read and write speeds. Benchmarked in the article above, these drives are able to do a sustained transfer upwards of 40mbyte/sec. This is on-par with low end desktop hard drives, and is definitely an item of interest for those of you that use a laptop as a replacement desktop.