Capacity: The amount of data that the disk can store. Usually 100's of GB's or TB's.- Cache: A small memory chip that stores a fraction of frequently accessed data that can be accessed extremely fast. Usually 8 or 16 or 32 or 64 MB.
- Spin Speed: The speed at which the hard disk platter rotates. Usually, 5400 or 7200 or 10000 rpm.
- Average Seek Time: The average time in which the R/W head can be positioned over the requested track for random read/write requests. Usually, ~8-10 ms.
- Average Latency: The average time for the disk to rotate the platter and position the correct sector under the R/W head. Usually, ~3-5 ms.
- Interface: The interface that the hard disk uses and the port that it will use to connect to the system. The interfaces also have transfer speeds of their own. For example, a max. of 167 MBps for IDE, 600 MBps for SATA.
Specifications of a Hard Disk
Hard Disks have a few performance specifications that a buyer must always know accurately before purchasing the hard disk. Better specs will obviously make the system perform faster. The specifications are: