Doesn't actually appear to be a Solid State Drive. It appears to be a HDD with a solid state cache. http://www.anandtech.com/show/3734/seagates-momentus-xt-revi... : Simply put a Hybrid HDD is a mechanical drive with some NAND flash on it that is automatically used by the drive to store data for quicker access. A hybrid drive really just attempts to do what my setup of two drives (SSD + HDD) does manually: put small, frequently used data on NAND flash and put larger, less frequently used data on platters.