What's the hard drive?

1.1956 years, IBM's IBM RAMAC is the prototype of a modern hard disk, it is equivalent to two refrigerator volume, but its storage capacity of only 5MB. 1973 IBM 3340 came out, it has "Winchest" this nickname, from his two 30MB storage unit, just the famous "Winchest rifle" caliber and the amount of ammunition. At this point, the basic structure of the hard disk is established.

In 2.198, two former IBM employees created a 5.25-inch 5MB hard drive, the first desktop-oriented product, and the company is Seagate (SEAGATE).

At the end of the 3.80, the introduction of Mr (Magneto resistive reluctance) technology by IBM led to a significant increase in the magnetic head sensitivity, which increased the storage density of the platters by dozens of times times the 20Mbpsi (bit/per square inch), which laid the foundation for a huge increase in HDD capacity. IBM applied the technology to launch its first 3.5-inch 1GB hard Drive in 1991.

From 4.197 to 1991, the storage density of the hard disk platters grew at an annual rate of 25%~30%, from 1991 to 60%~80%, and up to 100% or even 200%, from the astonishing speed that began in 1997 thanks to IBM's GMR (Giant Magneto resistive, giant reluctance) technology, which further enhance the magnetic head sensitivity, thereby increasing the storage density.

5.1995 years, to tie in with Intel's LX chipset, Quantum and Intel jointly released the UDMA 33 interface--eide Standard to upgrade the original interface data transfer rate from 16.6mb/s to 33mb/s the same year, Seagate developed liquid bearings (FDB, Fluid Dynamic bearing) motor. The so-called fdb refers to the gyroscope technology introduced to the hard disk production, with a thickness equivalent to one-tenth of the hair diameter of the oil film to replace the metal bearings, reduce the hard disk noise and calorific value.

6.1996 years, Seagate buys Connor (Conner peripherals).

7.1998 years February, UDMA66 specifications available.

8.2 Years October, Maxtor acquisition of Kun Teng.

Hitachi Global Storage Technology (Hitachi Global Storage Technologies, Hitachi GST) was set up in January to complete the 2.05 billion dollar acquisition of the IBM Hard Drive Division plan, 9.2003.

10.2005 Hitachi and Seagate have announced the beginning of a massive use of disk vertical write technology (perpendicular recording), which will change the magnetic field parallel to the disc to a vertical (90 degree) and make fuller use of the storage space.

11.2005 year December 21, HDD maker Seagate announced the acquisition of Maxtor.

12.2007 years January, Hitachi Global storage technology announced that it would sell the world's first 1Terabyte hard drive, a year later than the original scheduled time. The hard drive is priced at 399 dollars and can be purchased on average 2.75GB of hard disk space per dollar.

13.2007 years November, the Maxtor hard drive factory's preformatted hard drive, was found to have been implanted to steal online games of the account and password Trojan.

In December, Hitachi Global storage technology announced that it would launch a 3TB, 2TB and 1.5TB Deskstar 7k3000 hard Drive series to global OEM manufacturers and some distribution partners.

15.2011 years early March 8, the WD Western Data Company announced that it would invest $4.3 billion in cash plus stock to acquire a Hitachi wholly owned subsidiary, Hitachi Global Storage Technology (HGST), a world-class hard drive manufacturer.

Hard Disk Interface

Ata

Full name Advanced Technology attachment, is the traditional 40-pin with the port data cable to connect the motherboard and hard disk, the maximum external interface speed for the 133mb/s, because of the interference and the line is too poor, and line space, adverse computer cooling, will gradually be SATA Replaced.

Ide

IDE's English is all called "Integrated Drive Electronics", namely "Electronic Integrated Drive", commonly known as Pata and the mouth.

Sata

The use of SATA (serial ATA) port hard disk is also called serial hard disk, is the future of PC hard drive trend. In the 2001, the Serial ATA Commission, made up of Intel, APT, Dell, IBM, Seagate and Serial, officially established the ATA 1.0 specification, and in 2002, although serial ATA related equipment was not officially listed, serial The ATA Commission has preempted the Serial ATA 2.0 specification. Serial ATA uses serial connection, the Serial ATA bus uses the embedded clock signal, has the stronger error correcting ability, compared to the past its biggest difference is can carry on the transmission instruction (not only the data) to examine, if discovers the error will automatically correct, this greatly enhances the data transmission reliability. The serial interface also has the advantages of simple structure and hot-swappable support.

SATA II

SATA II is the chip giant Intel Intel and HDD giant Seagate Seagate developed on the basis of SATA, its main feature is that the external transmission rate from the SATA 150mb/s further increased to 300mb/s, in addition to the NCQ (Native Command Queuing, native command queue, Port multiplier, staggered start (staggered spin-up) and a series of technical features. However, not all SATA drives can use NCQ technology, except that the hard disk itself supports NCQ, and the SATA controller of the motherboard chipset is required to support NCQ.

Scsi

The English of SCSI is all called "Small Computer system Interface" (Small computer system interface), is a completely different interface with IDE (ATA), the IDE interface is standard interface of normal PC, and SCSI is not the interface specially designed for hard disk, is a kind of high-speed data transmission technology which is widely used in small machine. SCSI interface has a wide range of applications, multitasking, large bandwidth, low CPU usage, as well as hot Plug and so on, but the high price makes it difficult as the IDE hard drive, so the SCSI hard disk is mainly used in high-end servers and high-end workstations.

Fibre Channel

The English spelling of Fibre Channel is fibre Channel, same as the Scis interface. Fibre Channel was not originally designed for hard disk design and development of interface technology, is designed for the network system, but with the storage system on the speed of the need to gradually apply to the hard disk system. The Fibre Channel hard disk is developed to improve the speed and flexibility of the multi-disk storage system, and its appearance greatly improves the communication speed of the multi-disk system.　　The main characteristics of Fibre Channel are: hot-pluggable, high-speed bandwidth, remote connection, large number of connected devices. Fibre Channel is designed for the environment of a multi-disk system such as a server, which can meet the requirements of high data transmission rates for high-end workstations, servers, mass storage subnets, and peripherals through hubs, switches and point-to-point connections for two-way, serial data communication systems.

SAS interface

SAS (serial Attached SCSI), serial attached SCSI, is the next generation of SCSI technology, and is the same as the current serial ATA (SATA) hard drive, using serial technology to achieve higher transmission speed and improve internal space by shortening the link line. SAS is a new interface developed after the parallel SCSI interface. This interface is designed to improve the performance, availability, and extensibility of the storage system and to provide compatibility with SATA hard drives.