The HP Z820 has an HDD storage media which is faster than most many processor cores PCs that were launched around the same time as it. Most similar spec desktop computers that were released more than two years ago have a Flash storage media. A Hard Disk Drive (HDD) is the traditional storage method for computers. A HDD stores the information on magnetic disks. HDD drives are cheap, but they are slower than Flash and SSD bases storage systems.
This computer's storage speed (HDD) is in fact the worst storage speed amongst all personal computers of this type and age.
Amongst comparable types of computer the best storage speed is SSD.