Capacity and access speed of hard disk, Computer Engineering

Assignment Help:

Capacity and access speed:

PC hard disk drive capacity (measured in GB). The vertical axis is logarithmic, so the accurate line corresponds to exponential growth.

 By using  rigid  disks  and  sealing  the  unit  permit  much  tighter  tolerances  than  in  a  floppy  disk  drive. As a result, hard disk drives can store more data than floppy disk drives and may access and transmit it quicker.

  • The speediest  -enterprise? HDDs spin at 10,000 or 15,000 rpm, and may gain sequential  media transfer speeds above the 1.6 Gbit/s. and a sustained transfer rate up to 1 Gbit/s. Drives running at 10,000
  • A classic "desktop HDD" must store between 120 GB and 2 TB although rarely above 500GB of data
  • As of date April 2009, the highest power consumer HDDs is 2 TB.
  • (based on US market data rotate at 5,400 to 10,000 rpm, and contain a media transfer rate of 1 Gbit/s or higher. (1 GB = 109 B; 1 Gbit/s = 109 bit/s)or 15,000 rpm use smaller platters to mitigate improved power requirements (as they have less air drag) and therefore usually have lower capacity than the uppermost capacity desktop drives.
  • "Mobile HDDs", for example laptop HDDs, that are physically smaller than their enterprise counterparts and desktop, tend to be slower and have lower capacity. A typical mobile HDD spins at 5,400 rpm, having 7,200 rpm models available for a slight price premium. Due to physically smaller platter(s) , mobile HDDs usually have lower capacity than their physically larger counterparts.

The exponential increases in data access speeds of HDDs and disk space and have enabled the commercial viability of consumer products that need large storage capacities, such as digital audio players  and digital video recorders and.

The major way to decrease access time is to amplify rotational speed, so reducing rotational delay, though the major way to increase and storage capacity and throughput is to increase areal density. Based on historic trends, analysts guess a future growth in HDD bit compactness (and therefore capacity) of about 40% per year. Access times have not kept up having throughput increases, which themselves have not kept up with increase in storage capacity.

First 3.5″ HDD marketed as capable to store 1 TB was the Hitachi Desk star 7K1000. It have 5 platters at about 200 GB each, providing 1 TB (935.5 GiB) of usable space; note the dissimilarity among its capacity in decimal units (1 TB = 1012  bytes) and binary units (1 TiB = 1024 GiB = 240  bytes). 


Related Discussions:- Capacity and access speed of hard disk

What is the pcm pulse or symbol transmission rate, An analog information si...

An analog information signal, whose maximum frequency is 6000Hz, is to be transmitted using a PCM system. The quantization error must not exceed the ±1 % of the peak-topeak analog

Illustrate the ftp commands, Q. Illustrate the FTP commands? FTP includ...

Q. Illustrate the FTP commands? FTP includes many commands however only few are used to retrieve a file. A user is required to understand the three basic commands to connect to

Power supply in computer system, Q. Power supply in computer system? Co...

Q. Power supply in computer system? Computer operate electronically- either by power supply attained from your electric plug or batteries in case of portable computers. Though

Lfu, advantages of lfu

advantages of lfu

Centres of keycaps, A full size keyboard has distance between centres of ke...

A full size keyboard has distance between centres of keycaps (keys) like 19mm (0.75in).The keycaps have a top of nearly 0.5in (12.5in) that is shaped as a sort of dish to help you

State the benefits of encapsulation, State The Benefits of Encapsulation ...

State The Benefits of Encapsulation To hide the details of a class, you can declare that data or implementation in the private part of class so that other class clients will n

State the selective clear - logic micro operations, State the SELECTIVE CLE...

State the SELECTIVE CLEAR - logic micro operations The selective-clear operation clears to 0 bits in register A only  where there are corresponding 1's in the register B. For

What are rimm, What are RIMM? RDRAM chips can be assembled into larger ...

What are RIMM? RDRAM chips can be assembled into larger modules known as RIMM. It can hold up to 16 RDRAM

Define object oriented modelling, Object oriented modelling Object ori...

Object oriented modelling Object oriented modelling is entirely a new way of thinking about queries. This methodology is all about visualizing the things by using models organ

Diffrentiate between non-relocatable & relocatable programs, How non-reloca...

How non-relocatable programs are different from relocatable programs? Non relocatable program: It is one that cannot be made to execute in any type of area of storage other t

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd