The DELL OptiPlex 9020 has an SSD storage media which is faster than most medium processor cores computers that are a comparable age to it. Most similar spec PCs that have been around for around the same time as it have an HDD storage media. 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.
This PC's storage speed (SSD) is in fact the best storage speed across all personal computers of this type and age.
An HDD storage media is the worst storage speed across comparable types of PC.