機(jī)械硬盤---討論

easylife

原帖由 深南大道 于 2008-11-20 00:19 發(fā)表
+ s9 z) q1 a6 F! @4 }7 [$ X9 T8 G原來伊凡兄也深受無塵室之苦啊
剛畢業(yè)是忍受了半年,，現(xiàn)在偶爾進(jìn)下無塵室,。
6 _' p9 _/ @. H) K# U  P機(jī)械硬盤這個(gè)東西，我們能搞定里面的軸承就算阿彌陀佛了
固態(tài)硬盤,，掉電會(huì)不會(huì)影響它所存儲(chǔ)的數(shù)據(jù)呢,？

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U盤算是固態(tài)硬盤的前期簡(jiǎn)化版, 存儲(chǔ)好了的數(shù)據(jù)是不會(huì)丟的.

easylife

原帖由 螺旋線 于 2008-11-20 09:14 發(fā)表
電子硬盤早就在用，比如工控機(jī)上,，只是容量小,。
# ~# a0 _# e/ |# f8 l電子硬盤替代機(jī)械硬盤是一定的。

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其實(shí)大約二十年前就有人說過機(jī)械硬盤將要被芯片存儲(chǔ)器取代,
但機(jī)械硬盤又堅(jiān)持發(fā)展了二十多年,
3 B2 d# F: d( r" E: f甚至在90年代后期迎來其行業(yè)發(fā)展的高峰期--那時(shí)候昆騰的待遇和環(huán)境和現(xiàn)在的GOOGLE相似,
" ~. X+ ?# K  K% h; S) t而如今機(jī)械硬盤技術(shù)前景不明,幾大生產(chǎn)商低價(jià)慘烈搶占市份額,有的公司運(yùn)營(yíng)舉步為艱,行業(yè)發(fā)展前景不太樂觀.
也許幾年之后機(jī)械硬盤這個(gè)機(jī)電高度結(jié)合的高科技產(chǎn)物將消失在大家的視線中,只剩下一段可以追憶的歷史....
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想想80年代全世界80多家硬盤生產(chǎn)商,到如今的希捷,西數(shù),日立,東芝,富士通,三星和份額極少的易拓共7家公司,
硬盤行業(yè)的競(jìng)爭(zhēng)相當(dāng)殘酷

easylife

Hard Disk Drives

The hard disk drive in your system is the "data center" of the PC. It is here that all of your programs and data are stored between the occasions that you use the computer. Your hard disk (or disks) are the most important of the various types of permanent storage used in PCs (the others being floppy disks and other storage media such as CD-ROMs, tapes, removable drives, etc.) The hard disk differs from the others primarily in three ways: size (usually larger), speed (usually faster) and permanence (usually fixed in the PC and not removable).
  `/ v( p- r4 o$ j9 F9 b' THard disk drives are almost as amazing as microprocessors in terms of the technology they use and how much progress they have made in terms of capacity, speed, and price in the last 20 years. The first PC hard disks had a capacity of 10 megabytes and a cost of over $100 per MB. Modern hard disks have capacities approaching 100 gigabytes and a cost of less than 1 cent per MB! This represents an improvement of 1,000,000% in just under 20 years, or around 67% cumulative improvement per year. At the same time, the speed of the hard disk and its interfaces have increased dramatically as well.
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6 Z, g5 @; U9 N5 l$ ?Your hard disk plays a significant role in the following important aspects of your computer system:
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• Performance: The hard disk plays a very important role in overall system performance, probably more than most people recognize (though that is changing now as hard drives get more of the attention they deserve). The speed at which the PC boots up and programs load is directly related to hard disk speed. The hard disk's performance is also critical when multitasking is being used or when processing large amounts of data such as graphics work, editing sound and video, or working with databases.
• Storage Capacity: This is kind of obvious, but a bigger hard disk lets you store more programs and data.
• Software Support: Newer software needs more space and faster hard disks to load it efficiently. It's easy to remember when 1 GB was a lot of disk space; heck, it's even easy to remember when 100 MB was a lot of disk space! Now a PC with even 1 GB is considered by many to be "crippled", since it can barely hold modern (inflated) operating system files and a complement of standard business software.
• Reliability: One way to assess the importance of an item of hardware is to consider how much grief is caused if it fails. By this standard, the hard disk is the most important component by a long shot. As I often say, hardware can be replaced, but data cannot. A good quality hard disk, combined with smart maintenance and backup habits, can help ensure that the nightmare of data loss doesn't become part of your life.

This chapter takes a very detailed look at hard disks and how they work. This includes a full dissection of the internal components in the drive, a look at how data is formatted and stored, a discussion of performance issues, and a full analysis of the two main interfaces used to connect hard disks to the rest of the PC. A discussion is also included about the many confusing issues regarding hard disks and BIOS versions, and support for the newer and larger hard disks currently on the market. Finally, a full description is given of logical hard disk structures and the functioning of the FAT and NTFS file systems, by far the most popular currently used by PCs.
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硬盤是電腦的數(shù)據(jù)中心....
/ B- U; z7 z! W& \7 G) |# ?明天翻譯

5 n# q3 i2 r2 a1 w+ [+ i[ 本帖最后由 easylife 于 2008-12-31 14:07 編輯 ]

胡雷

不太了解啊 看眼界了

easylife

原帖由 easylife 于 2008-11-22 02:18 發(fā)表
Hard Disk Drives
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$ U6 A. p+ h7 ^! t. f- ?The hard disk drive in your system is the "data center" of the PC. It is here that all of your programs and data are stored between the occasions that you use the computer. Your ha ...

硬盤在電腦中起著數(shù)據(jù)中心的作用。它儲(chǔ)存了你使用電腦時(shí)所需要的一切程序和數(shù)據(jù),。硬盤是電腦里面永久性存儲(chǔ)數(shù)據(jù)設(shè)備中最重要的存儲(chǔ)設(shè)備（其他存儲(chǔ)設(shè)備有軟盤,，和其它存儲(chǔ)介質(zhì)如光盤，磁帶,，移動(dòng)硬盤等）,。硬盤在三個(gè)方面有別于其他存儲(chǔ)設(shè)備：尺寸（經(jīng)常較其他的大），速度（較快）和持久性（它經(jīng)常被固定在電腦里面并且不會(huì)被移動(dòng)）,。
, v, L" \, S& O! m  n在硬盤所采用的技術(shù),，和它在這最近20年里容量，速度及價(jià)格方面所發(fā)生的變化，可以說幾乎和微處理器（的發(fā)展歷程）一樣令人驚嘆,。
2 I* }9 Q  q$ ^第一臺(tái)個(gè)人電腦的容量只有10MB,，并且它的價(jià)格是100美圓每MB，
( ?7 [* u4 ]  ~1 `0 L5 n7 v而現(xiàn)代硬盤有接近100GB的容量,，價(jià)格低于1美分/MB�,。ㄗⅲ淮似�文章發(fā)表于大約在2005年）這些代表著在將近20年里,，（硬盤）容量有1,000,000%,，或者說每年近67%的累積增長(zhǎng)。與此同時(shí),，硬盤在它的速度和它的接口方面也取得了極大的進(jìn)步,。


硬盤在電腦系統(tǒng)里的如下方面扮演著重要的角色：
性能：硬盤在系統(tǒng)性能方面有著舉足輕重的地位，可能遠(yuǎn)遠(yuǎn)高于大多數(shù)人們所認(rèn)識(shí)到的（雖然這種情況正在改變,，硬盤現(xiàn)在得到了它應(yīng)該得到的關(guān)注）,。系統(tǒng)啟動(dòng)和程序載入的速度直接和硬盤的速度相關(guān)。當(dāng)系統(tǒng)執(zhí)行多任務(wù),，或者處理大量的數(shù)據(jù)如圖形方面的工作,，音頻和視頻編輯，及數(shù)據(jù)庫(kù)處理時(shí),，硬盤的性能也是個(gè)關(guān)鍵的影響效率的因素,。
存儲(chǔ)容量：顯而易見，更大的硬盤可以允許你儲(chǔ)存更多的程序和數(shù)據(jù),。
9 O7 h) n3 J  k- K% m9 ~支持軟件：新的程序需要更多的空間和更快的硬盤來使得它能被有效率地載入,。大家還清楚的記得不久前1GB意味著相當(dāng)大的存儲(chǔ)空間，甚至也還清楚的記得沒多久以前100MB對(duì)人們來說也是相當(dāng)大的磁盤存儲(chǔ)空間,。而現(xiàn)在是配備著1GB硬盤的電腦會(huì)被人們認(rèn)為是相當(dāng)不適用的,，因?yàn)樗�的存�?chǔ)容量還不能裝下現(xiàn)在臃腫的操作系統(tǒng)和一些必備的標(biāo)準(zhǔn)商業(yè)軟件。
! f# Y0 U$ x/ Y8 V. J) e3 V: h可靠性：評(píng)估硬盤重要性的一種辦法是想象下如果硬盤損壞了它將造成多大的損失,。根據(jù)這個(gè)標(biāo)準(zhǔn),，長(zhǎng)期來說硬盤是電腦里面最重要的部件，硬件能替換,，但數(shù)據(jù)是不能的,。一個(gè)質(zhì)量可靠的硬盤，加上適當(dāng)?shù)木S護(hù)和備份的好習(xí)慣,，能確保數(shù)據(jù)丟失的噩夢(mèng)不會(huì)發(fā)生在你的身上。

接下來將詳細(xì)介紹下硬盤結(jié)構(gòu)和它如何工作,。接下來會(huì)將硬盤內(nèi)部組件結(jié)構(gòu)展現(xiàn)在大家眼前,，介紹數(shù)據(jù)怎樣被格式化和儲(chǔ)存，及關(guān)于性能的討論,，并詳細(xì)分析將硬盤連接到電腦其他器件上去的兩中主要的接口,。同時(shí)也將包括…..

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[ 本帖最后由 easylife 于 2008-12-31 14:08 編輯 ]

easylife

A Brief History of the Hard Disk Drive
Hard disks are one of the most important and also one of the most interesting components within the PC. They have a long and interesting history dating back to the early 1950s. Perhaps one reason that I find them so fascinating is how well engineers over the last few decades have done at improving them in every respect: reliability, capacity, speed, power usage, and more.
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..chart...
; I; u2 c% u. l7 p: v' t5 qThis excellent chart (shown in attached picture) shows the evolution of IBM hard disks over the past 15 years. Several
7 A: E& ~4 t# `different form factors are illustrated, showing the progress that they have made over the
# c0 T/ e. b5 vyears in terms of capacity, along with projections for the future. 250 GB hard disks in
2 v7 G9 I" U" _3 I, e! ^laptops in five years? Based on past history, there's a good chance that it will in fact happen!
+ h# p4 T8 X2 W4 @3 f, P5 tNote that the scale on the left is logarithmic, not linear, and PC hard disks have one actuator.

硬盤歷史簡(jiǎn)述
8 A$ Y: \8 X2 h硬盤是個(gè)人電腦里面最重要也是最有意思的組件,。它們有著可追溯到20世紀(jì)50年代的漫長(zhǎng)而有趣的歷史。我發(fā)現(xiàn)它們之所以如此令人著迷的原因之一可能是,，工程師們?cè)诙潭痰膸资�年�?nèi)在硬盤的可靠性,，容量，速度,，能耗等方面取得了可喜的成績(jī),。

- y  {* U& ]) O& i0 y0 K+ x3 i7 K4 O這張圖表顯示了IBM硬盤在過去的15年里面取得的進(jìn)步。表中列出了幾個(gè)不同的外形尺寸,，顯示了在過去這些年里在容量方面取得的進(jìn)步,，還有對(duì)未來的預(yù)測(cè)。5年里出現(xiàn)250GB的筆記本硬盤,？基于過去的歷史,，這確實(shí)是很有可能發(fā)生的（注：實(shí)際上已經(jīng)成為現(xiàn)實(shí)，文章是2005年發(fā)布）,。請(qǐng)注意圖表左邊的標(biāo)尺刻度是對(duì)數(shù)的,，不是線性的，而且是基于硬盤只有一個(gè)磁頭臂組（HSA）,。

[ 本帖最后由 easylife 于 2008-11-22 23:27 編輯 ]

easylife

Life Without Hard Disk Drives
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It's very hard for modern computer users to even consider what "computer life" would be like without hard disk drives. After all, most of us now have billions and billions of bytes of information ready at our fingertips (apologies to Carl Sagan... ;^) ). What was using a computer like before we had hard disk drives? In a word... inconvenient.
7 A$ e( r8 a8 N  J8 [/ dSome of the very earliest computers had no storage at all. Each time you wanted to run a program you would have to enter the program manually. Needless to say, this was a major pain in the butt. Even more than that, it made most of what we consider today to be computing impossible, since there was no easy to way to have a computer work with the same data over and over again. It was quickly realized that some sort of permanent storage was necessary if computers were to become truly useful tools.
% d4 L: c+ f" F4 l0 ]The first storage medium used on computers was actually paper. Programs and data were recorded using holes punched into paper tape or punch cards. A special reader used a beam of light to scan the cards or tape; where a hole was found it read a "1", and where the paper blocked the sensor, a "0" (or vice-versa). This was a pretty simple arrangement. I remember using a punch station, which was like a workstation where you typed characters and the machine punched the holes into the cards. While a great improvement over nothing, these cards were still very inconvenient to use. You basically had to write the entire program from scratch on paper, and get it working in your mind before you started trying to put it onto cards, because if you made a mistake you had to re-punch many of the cards. It was very hard to visualize what you were working with. The card readers had a tendency to jam (the old one at my high school was nicknamed the "IBM 1443 card chewer".) And heaven help you if you dropped a stack of cards on the floor... Still however, paper was used as the primary storage medium for many years.
0 C, i( d  l0 @  i  XThe next big advance over paper was the creation of magnetic tape. Almost everyone has at least seen pictures of the large reels of tape used in older computers. Recording information in a similar to way to how audio is recorded on a tape, these magnetic tapes were much more flexible, durable and faster than paper tape or punch cards. Of course, tape is still used today on modern computers, but as a form of offline or secondary storage. Before hard disks, they were the primary storage for some computers. Their primary disadvantage is that they must be read linearly; it can take minutes to move from one end of the tape to the other, making random access impractical.
Warning: Nostalgia mode activated. Be very afraid.
( D  s/ I4 s  _% ~' y0 |Personal computers developed much later than the early, large mainframes, and were therefore the beneficiaries of advancements in storage technologies fairly early on in their existence. My first computer was purchased for me by my parents in 1980: an Apple ][. A great little machine for learning on, using it gave me a profound appreciation for the importance of storage: because it had none! No hard disk drive, not even a floppy disk drive. My choices were to type in programs by hand (which I did sometimes) or try to load them from a cassette tape. Yes, an audio cassette tape. If you thought modern computer tape drives were unreliable, you should have tried getting that to work! (Oh, and I also had to walk barefoot through three feet of snow to get to school... uphill both ways!)
- a$ v1 G1 h1 h+ E: aI later purchased a low-density, single-sided floppy disk drive for my Apple. Boy, what a feeling of freedom that was! I could load and save programs and data easily, something I could never do before. That disk drive cost C$700 (back when the Canadian dollar was worth not much less than the U.S. dollar.) The biggest advantages of floppy disks over tapes are the ability to randomly access the data, and much better portability. They don't have nearly as much capacity however.
The first IBM PCs also had no hard disk drive, but rather employed one or two floppy disk drives. While of course far better than nothing, floppy disk drives were slow, small in capacity and relatively unreliable compared to even the earliest hard disks.

[ 本帖最后由 easylife 于 2008-11-22 23:34 編輯 ]

easylife

對(duì)于現(xiàn)在電腦的使用者們來說,，很難想象沒有硬盤的“電腦”生活會(huì)變成什么樣子,。畢竟，現(xiàn)在大多數(shù)人手中（輕松）掌握著數(shù)以億記字節(jié)的數(shù)據(jù)和信息,。那沒有硬盤之前使用電腦是個(gè)什么樣子的情況,？一個(gè)詞—--不便。
一些最早期的電腦根本沒有存儲(chǔ)設(shè)備,。每次當(dāng)你想運(yùn)行一個(gè)程序時(shí),，你必須手工輸入程序。不用說,，這是件很痛苦的事情,。更麻煩的是，這樣的操作方式使得我們今天稱做計(jì)算的工作無法進(jìn)行,，因?yàn)樵谕�一臺(tái)電腦上多次使用同樣的數(shù)據(jù)進(jìn)行計(jì)算不是件容易的事情,。很快人們認(rèn)識(shí)到，如果想讓計(jì)算機(jī)變成真正有用的工具,，永久性的存儲(chǔ)是必須的,。
6 W! y# `/ S; T# b& B* O早期的存儲(chǔ)介質(zhì)是真正的紙。程序和數(shù)據(jù)記錄通過在紙張或者卡片上沖孔來實(shí)現(xiàn)。特殊的讀取設(shè)備使用一束光來掃描卡片或者紙帶,，但讀到孔時(shí)記錄為1,，當(dāng)某位置沒有孔而光透不過去時(shí)，讀為0（或者反之）,。這種方式是非常簡(jiǎn)單的,，我還記得使用過的沖孔機(jī)器，它就象是一個(gè)你輸入字符然后機(jī)器在紙片上打孔的工作站,。其實(shí)這個(gè)巨大的改進(jìn)等于無用,，這樣紙帶和卡片使用起來還是非常不方便�,；�本上你必須先將整個(gè)程序從無到有地在白紙上寫出來,，在腦海里考慮好，然后才去輸入,，因?yàn)槿绻�你犯了錯(cuò)的必須重新沖孔許多的紙帶,。很難去想象你是在和什么打交道，卡片讀取器經(jīng)常堵塞（在我的高中學(xué)校將這種老機(jī)器戲稱為“IBM 1443 卡片咀嚼器”）,。如果你把一卷紙帶失手掉在地上了的話,，那你的請(qǐng)求神仙來搭救你了，呵呵,。盡管如此,，紙帶還是作為主要的存儲(chǔ)介質(zhì)使用了很多年。
8 k" t& v8 ]& }0 J2 w% B紙帶之后下一個(gè)大的改進(jìn)是磁帶的發(fā)明,。幾乎所有人至少見過使用在舊電腦中的大盤磁帶的圖片,。信息的記錄類似于在錄音磁帶上錄音的方式，磁帶相對(duì)紙帶和卡片來說更軟,，更耐用和速度更快,。當(dāng)然，磁帶在現(xiàn)代的電腦中仍然在使用,，但是是作為離線或者第二存儲(chǔ)設(shè)備的形式,。在硬盤出現(xiàn)之前，他們是電腦主要的存儲(chǔ)設(shè)備,，他們主要的缺點(diǎn)是必須被線性的讀取,，從磁帶的一端到另一端要花費(fèi)幾分鐘的時(shí)間，這使得隨機(jī)讀取不可行,。
0 z: l. |; O/ \: f; H: b個(gè)人電腦是在早期大型電腦發(fā)展之后才開發(fā)出來的,，因此它從出現(xiàn)就相當(dāng)早的成為了存儲(chǔ)技術(shù)進(jìn)步的受益者。我的第一臺(tái)電腦是我父母在1980年給我買的,，Apple II,一臺(tái)不錯(cuò)的用于學(xué)習(xí)的小機(jī)器,，通過使用它使我對(duì)存儲(chǔ)的重要性有非常深刻的認(rèn)識(shí),，因?yàn)檫@臺(tái)機(jī)器根本就沒有存儲(chǔ)設(shè)備！沒硬盤,，甚至沒有軟盤。我的選擇是手工輸入程序（過去經(jīng)常這樣做）,，或者試著從磁帶上下載這些程序,。告訴你那確實(shí)是磁帶，就是錄音磁帶那種,�,！�..
3 q$ j9 T7 M. l6 S: I  o后來我為我的蘋果機(jī)買了一張低密度，單面的軟盤,。朋友,，那時(shí)候知道什么叫做自由！我能輕松地下載和保存程序,，而有些是我以前無法做到的,。那張軟盤花了我700加元（那時(shí)候加元和美圓差不多）。相對(duì)磁帶來說,，軟盤的最大優(yōu)點(diǎn)就是能夠隨意地讀取數(shù)據(jù),，而且攜帶也方便些，雖然它們沒有和磁帶那么多的容量,。
6 I( Z. Z* N! u第一臺(tái)IBM個(gè)人電腦也沒有硬盤,，但配備有一張或者兩張軟盤，當(dāng)然這些總比沒有好,，軟盤較慢,，容量小，而且哪怕和最早期的硬盤相比,，它的可靠性也是較差的,。

easylife

Early Disk Drives

: o/ k4 V. U. |8 _: g# mThe very first disk drives were of course experiments. Researchers, particularly those at IBM, were working with a number of different technologies and concepts to try to develop a disk drive that would be feasible for commercial development. In fact, the very first drives were not "disk drives" at all--they used rotating cylindrical drums, upon which the magnetic patterns of data were stored. The drums were large and hard to work with.
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The earliest "true" hard disks had the heads of the hard disk in contact with the surface of the disk. This was done to allow the low-sensitivity electronics of the day to be able to better read the magnetic fields on the surface of the disk. Unfortunately, manufacturing techniques were not nearly as sophisticated as they are now, and it was not possible to get the disk's surface as smooth as would be necessary to allow the head to slide smoothly over the surface of the disk at high speed while in contact with it. Over time the heads would wear out, or wear out the magnetic coating on the surface of the disk.

% G2 A% j/ {- d# qThe key technological breakthrough that enabled the creation of the modern hard disk came in the 1950s. IBM engineers realized that with the proper design the heads could be suspended above the surface of the disk and read the bits as they passed underneath. With this critical discovery that contact with the surface of the disk was not necessary, the basis for the modern hard disk was born.

The very first production hard disk was the IBM 305 RAMAC (Random Access Method of Accounting and Control), introduced on September 13, 1956. This beastie stored 5 million characters (approximately five megabytes, but a "character" in those days was only seven bits, not eight) on a whopping 50 disks, each 24 inches in diameter! Its areal density was about 2,000 bits per square inch; in comparison, today's drives have areal densities measured in billions of bits per square inch. The data transfer rate of this first drive was an impressive 8,800 bytes per second.

Over the succeeding years, the technology improved incrementally; areal density, capacity and performance all increased. In 1962, IBM introduced the model 1301 Advanced Disk File.  The key advance of this disk drive was the creation of heads that floated, or flew, above the surface of the disk on an "air bearing", reducing the distance from the heads to the surface of the disks from 800 to 250 microinches.

. ~, g  K* r4 N$ j0 w/ O$ yIn 1973, IBM introduced the model 3340 disk drive, which is commonly considered to be the father of the modern hard disk. This unit had two separate spindles, one permanent and the other removable, each with a capacity of 30 MB. For this reason the disk was sometimes referred to as the "30-30". This name led to its being nicknamed the "Winchester" disk drive, after the famous "30-30" Winchester rifle. Using the first sealed internal environment and vastly improved "air bearing" technology, the Winchester disk drive greatly reduced the flying height of the disk: to only 17 microinches above the surface of the disk. Modern hard disks today still use many concepts first introduced in this early drive, and for this reason are sometimes still called "Winchester" drives.
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4 e: B. i8 W" [4 ~/ tThe first hard disk drive designed in the 5.25" form factor used in the first PCs was the Seagate ST-506. It featured four heads and a 5 MB capacity. IBM bypassed the ST-506 and chose the ST-412--a 10 MB disk in the same form factor--for the IBM PC/XT, making it the first hard disk drive widely used in the PC and PC-compatible world.

easylife

早期的硬盤
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: n9 E" N+ [" j/ B+ e, A) e" f% u最早期的硬盤當(dāng)然是試驗(yàn)品。研究人員,，特別是IBM的那些人,，在當(dāng)時(shí)正使用著一些不同的技術(shù)和概念，嘗試開發(fā)出適合于商業(yè)運(yùn)用的硬盤產(chǎn)品,。實(shí)際上,，最早期的驅(qū)動(dòng)器根本不是硬盤，它們使用旋轉(zhuǎn)的轉(zhuǎn)盤,，轉(zhuǎn)盤上涂敷磁性物質(zhì)存儲(chǔ)數(shù)據(jù),。轉(zhuǎn)盤非常大，操作起來比較困難,。最早期硬盤的磁頭和碟片是接觸的,，這樣的話可以使（相對(duì)今天來說）敏感度較低的電子元器件在讀取碟片表面磁場(chǎng)信號(hào)時(shí)變得容易些,。但不幸的事情是，那時(shí)侯的制造技術(shù)不像現(xiàn)在這樣先進(jìn),，因此不能將碟片的表面加工的足夠的光滑,，從而允許磁頭在高速運(yùn)動(dòng)并和碟片接觸時(shí)平穩(wěn)地在碟片表面滑動(dòng)。時(shí)間長(zhǎng)了后,，要么磁頭磨損,，要么導(dǎo)致碟片表面的磁性層磨損。
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0 W( o8 X9 c+ P關(guān)鍵技術(shù)的突破使得人們?cè)?0世紀(jì)50年代發(fā)明了現(xiàn)代硬盤,。 IBM的工程師意識(shí)到通過合適的設(shè)計(jì)可以使磁頭懸浮在盤片表面并讀取磁頭下方的數(shù)據(jù),。有了這個(gè)關(guān)鍵的發(fā)現(xiàn)后，磁頭并不一定要接觸盤片,，現(xiàn)在硬盤的雛形型出現(xiàn)了,。
- A8 S, f4 J" u# k7 W. c  d接下來這些年，技術(shù)不斷進(jìn)步,，面密度,，容量和性能都得到了提升。1962年,，IBM推出了1301高級(jí)磁盤文件模型,。這個(gè)硬盤關(guān)鍵的改進(jìn)是磁頭通過空氣軸承在磁盤表面懸浮或者說飛行，將磁頭到盤片的距離從800微英寸減少到250微英寸,。

1973年,，IBM推出了3340磁盤驅(qū)動(dòng)器----一般被普遍認(rèn)為是現(xiàn)在硬盤驅(qū)動(dòng)器的鼻祖。這個(gè)單元有兩個(gè)獨(dú)立的主軸馬達(dá),，一個(gè)是永久性安裝在里面而另一個(gè)是可移除的,，每個(gè)馬達(dá)都具有30MB的容量。由于這個(gè)原因這個(gè)硬盤有時(shí)又稱為“30-30”,，而這個(gè)名字又使得它擁有了另外一個(gè)別名“溫徹斯特”硬盤,，來源于著名的“30-30”溫徹斯特來復(fù)槍。首次采用內(nèi)部完全密封,，并且極大地改進(jìn)了空氣軸承技術(shù)的溫徹斯特硬盤極大地降低了飛行高度：距盤片表面只有17微英寸�,，F(xiàn)代硬盤仍然沿用著使用在早期硬盤上的許多概念，由于這個(gè)原因有時(shí)我們?nèi)苑Q他們?yōu)椤皽貜厮固亍彬?qū)動(dòng)器,。
使用在個(gè)人電腦上的第一個(gè)5.25英寸硬盤是希捷的ST-506,。它有四個(gè)磁頭，容量5MB,。IBM選擇了ST-412,，一個(gè)10MB容量的5.25英寸硬盤作為其IBM PC/XT的硬盤驅(qū)動(dòng)器，而并沒有選擇ST-506,，使得ST-41成為第一個(gè)廣泛使用在個(gè)人電腦及其兼容設(shè)備上的硬盤驅(qū)動(dòng)器,。

+ M5 Q) s  ~2 W4 E+ [[ 本帖最后由 easylife 于 2008-11-23 23:24 編輯 ]