WD/HGST DC HC550 3.5" 18 TB, 7.2K SAS 3 512MB - WUH721818AL5201

Detailed information

Characteristics

Disks with moving parts are generally slower than SSDs, however they have high capacities and have a better price per GB. Server disks are more reliable than desktop ones and reach higher MTBF numbers (mean time between failures).

Interface

When choosing a hard drive it's important to consider the choice of SATA, SAS, or NVMe disks. SATA and SAS disks are intended for both HDDs and SSDs and differ in their theoretical transfer speeds. NVMe disks are flash-based only and as such reach much higher read/write numbers and are also characterized by their very low latency.

Speed and Capacity

A key parameter in terms of hard drives is their RPM, which ranges between 5400 and 15000. This directly influences the speed of the drive and with that, its price. Today, more and more HDDs are being replaced by SSD solutions. SSDs are many times faster and their prices are starting to get closer to those of traditional HDDs. Their access times are also often faster and there's no wear when reading from the flash memory. The newest standard, NVMe, increases the quality of disks with flash memories even more and more hard drive manufacturers are starting to use it.

Product Specifications

Capacity: 18 TB
Form Factor: 3.5"
RPM: 7200rpm
Interface: SAS
Cache: 512MB