The HP 640 MT has an SSD storage media which is faster than the HDD storage media found on most many processor cores desktop computers that have been around for a similar time to it. Solid State Drives (SSD) store information in transistors on a circuit board rather than on optical or magnetic media. This has the advantage of being much faster than a traditional HDD drive.
An SSD storage media is actually the best storage speed amongst all recently released computers.
Amongst similar types of computer the worst storage speed is HDD.