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Quantum Bigfoot
The Quantum Bigfoot brand was a series of hard disk drives produced by Quantum Corp. from 1996 through the late 1990s. The Bigfoot series was notable for deviating from the standard form factor for hard drives. While most desktop hard drives at that time used a 3.5-inch physical format, Quantum Bigfoot drives used a larger 5.25-inch form factor more commonly seen in older hard drives, CD-ROM and other optical disc drives. This form factor allowed Quantum to increase the capacity of their hard drives without an increase in data density, thus lowering costs compared to a 3.5-inch drive with the same capacity. It also allowed manufacturers and owners to install the hard drive above or below the optical drive in the computer, as the typical computer had multiple 5.25-inch bays. Overview The main rationale behind the use of the 5.25-inch form factor was that the typical PC user already owns cases that supports 5.25-inch drives, and by using lower data densities and fewer moving par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hard Disk Drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored and retrieved in any order. HDDs are a type of non-volatile storage, retaining stored data when powered off. Modern HDDs are typically in the form of a small rectangular box. Introduced by IBM in 1956, HDDs were the dominant secondary storage device for general-purpose computers beginning in the early 1960s. HDDs maintained this position into the modern era of servers and personal computers, though personal computing devices produced in large volume, like cell phones and tablets, rely on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logical Block Addressing
Logical block addressing (LBA) is a common scheme used for specifying the location of blocks of data stored on computer storage devices, generally secondary storage systems such as hard disk drives. LBA is a particularly simple linear addressing scheme; blocks are located by an integer index, with the first block being LBA 0, the second LBA 1, and so on. The IDE standard included 22-bit LBA as an option, which was further extended to 28-bit with the release of ATA-1 (1994) and to 48-bit with the release of ATA-6 (2003), whereas the size of entries in on-disk and in-memory data structures holding the address is typically 32 or 64 bits. Most hard disk drives released after 1996 implement logical block addressing. Overview In logical block addressing, only one number is used to address data, and each linear base address describes a single block. The LBA scheme replaces earlier schemes which exposed the physical details of the storage device to the software of the operating sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hdparm
hdparm is a command line program for Linux to set and view ATA hard disk drive hardware parameters and test performance. It can set parameters such as drive caches, sleep mode, power management, acoustic management, and DMA settings. GParted and Parted Magic both include ''hdparm''. Changing hardware parameters from suboptimal conservative defaults to their optimal settings can improve performance greatly. For example, turning on DMA can, in some instances, double or triple data throughput. There is, however, no reliable method for determining the optimal settings for a given controller-drive combination, except careful trial and error. Depending on the given parameters, ''hdparm'' can cause computer crashes or render the data on the disk inaccessible. Usage examples hdparm has to be run with special privileges, otherwise it will either not be found or the requested actions will not be executed properly. Display information of the hard drive: sudo hdparm -I /dev/sda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Millisecond
A millisecond (from '' milli-'' and second; symbol: ms) is a unit of time in the International System of Units (SI) equal to one thousandth (0.001 or 10−3 or 1/1000) of a second and to 1000 microseconds. A unit of 10 milliseconds may be called a centisecond, and one of 100 milliseconds a decisecond, but these names are rarely used. To help compare orders of magnitude of different times, this page lists times between 10−3 seconds and 100 seconds (1 millisecond and one second). ''See also'' times of other orders of magnitude. Examples The Apollo Guidance Computer used metric units internally, with centiseconds used for time calculation and measurement. *1 millisecond (1 ms) – cycle time for frequency 1 kHz; duration of light for typical photo flash strobe; time taken for sound wave to travel about 34 cm; repetition interval of GPS C/A PN code *1 millisecond - time taken for light to travel 204.19 km in a single mode fiber optic cable for a wavelength o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Access Time
Access time is the time delay or latency between a request to an electronic system, and the access being completed or the requested data returned * In a computer, it is the time interval between the instant at which an instruction control unit initiates a call for data or a request to store data, and the instant at which delivery of the data is completed or the storage is started. See also * Memory latency * Mechanical latency * Rotational latency * Seek time Higher performance in hard disk drives comes from devices which have better performance characteristics. These performance characteristics can be grouped into two categories: access time and data transfer time (or rate). Access time The ''access ... References Network access {{compu-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Technology Attachment
Parallel ATA (PATA), originally , also known as IDE, is a standard interface designed for IBM PC-compatible computers. It was first developed by Western Digital and Compaq in 1986 for compatible hard drives and CD or DVD drives. The connection is used for storage devices such as hard disk drives, floppy disk drives, and optical disc drives in computers. The standard is maintained by the X3/INCITS committee. It uses the underlying (ATA) and Packet Interface ( ATAPI) standards. The Parallel ATA standard is the result of a long history of incremental technical development, which began with the original AT Attachment interface, developed for use in early PC AT equipment. The ATA interface itself evolved in several stages from Western Digital's original Integrated Drive Electronics (IDE) interface. As a result, many near-synonyms for ATA/ATAPI and its previous incarnations are still in common informal use, in particular Extended IDE (EIDE) and Ultra ATA (UATA). After the introdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spindle Speed
The phrase speeds and feeds or feeds and speeds refers to two separate velocities in machine tool practice, cutting speed and feed rate. They are often considered as a pair because of their combined effect on the cutting process. Each, however, can also be considered and analyzed in its own right. ''Cutting speed'' (also called ''surface speed'' or simply ''speed'') is the speed difference ( relative velocity) between the cutting tool and the surface of the workpiece it is operating on. It is expressed in units of distance across the workpiece surface per unit of time, typically surface feet per minute (sfm) or meters per minute (m/min). ''Feed rate'' (also often styled as a Compound (linguistics), solid compound, ''feedrate'', or called simply ''feed'') is the relative velocity at which the cutter is advanced along the workpiece; its vector is perpendicular to the vector of cutting speed. Feed rate units depend on the motion of the tool and workpiece; when the workpiece rota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
