Hard Drive Against Tape Drive
Prior to the introduction of hard drives, the main medium of storage used specially by mainframe computers is known as the Tape Drive. There are significant differences between the two storage mediums which include:
• Magnetic recording material on tape is coated on a thin plastic strip, hard drives utilize layered high precision aluminum or glass disk;
• The seek operation is faster on a hard drive compared to a tape drive;
• The head on a tape drive comes in contact with the media while on a hard drive there is no actual contact but flies over the media;
• A hard drive can store huge amounts of data in a relatively small space compared to a tape drive.
MTBF – Meaure of Reliability
Mean-Time-Between-Failure or MTBF is a term used to describe the reliability of the parts of a computer system from a technical standpoint describing reliability and is measured in hours. The higher this number the more reliable a computer part is. with respect to hard disk drives, particularly IDE drives this denotes the number of hours before it fails or parts of the electronics, motors and bearings can last without any failure. This is an older measure used by the computing industry when hard drives were still quite steeply priced with the best ones reserved fro use on servers and other high demand uses. Ide has long been replaced by the SATA standard which eliminates the thick IDE cable that blocks airflow within a computer’s casing preventing proper cooling.
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The IDE Hardisk
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Integrated Drive Electronics (IDE) hard disks have been around for quite a few years. Prior to these drives, hard disks were interfaced to a PC motherboard via an extension board known as a hard disk controller. The drive did most of the mechanical stuff and performed essential electronic/servo functions; the controller told it in detail what to do. The development of the IDE hard moved most of the electronics and firmware (low-level software on a chip) from the controller to a printed circuit board on the drive itself. In the process, a buffer/cache’ memory was added to the electronics to speed-up the process of reading and writing hard disk drive data. The drive got “smarter.” Overall costs went down and performance went up.
A much simpler board, usually identified as an IDE Controller, interfaced the IDE hard disk to the motherboard bus. The term IDE Controller is a misnomer. It is really nothing more than a bus interface and an interface and connector for the IDE cable going to the drive. The actual controller is on the drive. Â