From the source of computer noise, it can be roughly divided into three parts, namely, fan noise, hard disk noise and CD-ROM noise. In addition, some computers will have vibration noise.

The source of hard disk noise

Although noise is not a direct measure of hard disk performance, it is not a pleasant thing to hear a burst of hard disk noise. Looking at the development history of hard disk, we can find that the noise of hard disk is actually proportional to the rotational speed of hard disk: every time the rotational speed increases by one grade, the noise level will increase accordingly.

Although the 7200 rpm hard disk has been improved a lot and become the mainstream of the market, the noise is still higher than that of the 5400 rpm hard disk. Usually, there are two motors in the hard disk. One is the spindle motor that drives the hard disk to rotate. This kind of motor used to be the main source of noise and heat, but now many manufacturers have begun to use liquid bearing motors, using mucosal liquid oil bearings instead of balls, which can effectively reduce the noise and heat problems caused by metal friction.

At the same time, the liquid oil-bearing can also effectively absorb vibration, thus improving the anti-seismic ability of the hard disk, and thus improving the life and reliability of the hard disk. However, there is also a seek motor. Due to technical and cost reasons, the motor does not use liquid bearing motor, which is the sound we usually hear from the hard disk. With the acceleration of spindle motor speed, the seek motor can work harmoniously and exert its potential only after acceleration. At present, the noise of most hard disks is mainly caused by this seek motor, and the hard disks of different manufacturers have different sounds.

In order to reduce the hard disk noise, many hard disk manufacturers are really "eight immortals crossing the sea", combining soft and hard, and making their own killer. For example, in the aspect of "hardware", a new type of liquid bearing motor is adopted, the internal structure of hard disk is improved again, washers made of materials that absorb vibration and noise, sound insulation foam, etc. In the aspect of "software", their respective noise reduction technical schemes are introduced. Let's get a general idea of these methods.

1, liquid bearing motor technology

The spindle motor and seek motor inside the hard disk drive the operation of the hard disk, which is also the source of noise. Ball bearing motors were used in early hard disk motors. At that time, due to the low speed of the hard disk, the noise was very small. However, with the increase of hard disk speed, ball bearing motor has brought many problems, such as wear, temperature and noise increase, and has become the main source of hard disk noise, which obviously has not adapted to the requirements of hard disk development. In this case, hard disk manufacturers have successively introduced hard disks with new liquid bearing motors.

The technology of hydrodynamic bearing motor has been used in precision machinery industry in the past, and its technical core is to use mucosal liquid-oil bearings and replace balls with oil films. Compared with the traditional ball bearing hard disk, the advantages of liquid bearing hard disk are obvious. The first is noise reduction and cooling. Avoid the direct friction between the ball and the bearing metal surface, and minimize the noise and heat generation of the hard disk; The second is to reduce vibration and noise. Oil film can effectively absorb vibration and improve the seismic capacity of hard disk; The third is to reduce wear and improve the reliability and service life of hard disks.

Seagate produced the world's first FDB motor in 1996, and then introduced the first hard disk product with liquid bearing motor. So far, FDB cars have developed to the sixth generation. At present, desktop hard disk manufacturers Maituo, Seagate, Western Digital, Hitachi (formerly IBM hard disk), Samsung, notebook hard disk manufacturers Fujitsu, Toshiba, IBM and so on. Basically, there are hard disks with liquid bearings.

2 computer hard disk noise reduction strategy (2)

2, other hard disk noise reduction technology

In addition to the use of liquid bearing motor technology, major hard disk manufacturers also have their own unique "kung fu" to deal with hard disk noise. Let's take a look at the noise reduction technology of different brands of hard disks.

(1) Seagate hard disk noise reduction technology

Once upon a time, Seagate's IDE hard disk almost became synonymous with loud hard disk, but all this vanished with the introduction of barracuda ATA IV hard disk. The application of sound shielding technology (SBT) makes Seagate's hard disk the quietest IDE hard disk at present. Sound shielding technology includes the following items:

Soft acoustic wave hydrodynamic bearing technology: Soft acoustic wave motor is the core of sound shielding technology (SBT) of Seagate hard disk, and it is also a technological breakthrough appreciated by various computer users. According to the industry standard test, the noise emitted by the cool fish ATA IV single-disk model is only 2 bells when rotating, 2.4 bells when seeking, and the sound below 2.5 bells is inaudible to human ears.

SeaShield cover and soundproof foam: SeaShield cover is a metal baffle on one side of hard disk circuit, which together with soundproof foam can further reduce the possibility of noise leakage.

Rotary rectification technology: By controlling the working current waveform of the spindle motor, the start and stop of the motor are more stable and smooth.

Silent seek technology: mainly includes speed limit, acceleration limit, current shaping and timely seek. Because these technologies are complicated, I won't introduce them in detail here.

(2) Maxtor hard disk noise reduction technology.

Since the acquisition of Quantum, Maituo's hard disk business is booming. In addition to applying its own noise reduction technology, Maituo also adopted many technologies of Quantum Company, including QDT mute technology. The combination of powerful technologies makes Maituo's hard disk have higher technical content and competitiveness.

Maituo silent store technology: actually, this is not a new technology. Maituo put forward this noise reduction scheme long ago, which was called "acoustic management" at that time. The principle of this technology is to add a control program to the BIOS chip of the hard disk to artificially reduce the reaction speed of the magnetic head power arm, that is, to reduce the seek speed, thus reducing the noise.

Because this technology will slightly reduce the performance of the hard disk, and the noise problem was not very prominent when the 5400 rpm hard disk was the mainstream a few years ago, it was not applied until the 7200 rpm hard disk became the mainstream. Users can download the latest control program from Maituo official website, Maituo's AMSET utility, which is used for Maituo's hard disk with silent storage technology. Decompress the downloaded program to a floppy disk, and then use this floppy disk to start the computer and run the Amset program.

Amset.exe has four parameters, namely/Quiet,/Fast,/Check and/Close. /quiet mode can reduce hard disk noise, but it will reduce performance. /Fast mode allows a slight decrease in performance in exchange for noise reduction, but the noise reduction effect is not as good as that of/Silent mode; /check can check the current mute mode of the hard disk, /off will completely turn off the noise reduction function option, so that the hard disk can run at the best performance.

QuiteDriveTechnology used to be the hard disk mute technology that Quantum Company was proud of, but with the acquisition of Quantum Company by Maituo, this excellent technology naturally belongs to Maituo, which can control the hard disk noise below 3.0 rings.

3 computer hard disk noise reduction strategy (3)

(3)IBM hard disk noise reduction technology

As the initiator of Winchester disk structure that all desktop hard disks follow at present, IBM has always been in a very important position in the field of hard disks. However, since the second generation of Longteng, the problem of high hard disk repair rate has cast a shadow on IBM, and now IBM has sold the hard disk division to Hitachi, but in any case, the technical content of IBM's hard disk is beyond doubt.

Noise reduction technology of IBM Drive noise suppression system: When this technology is applied to IBM's desktop hard disk, it mainly includes ceramic spindle motor, improved voice coil motor and three-layer top cover to reduce noise transmission. With the application of these advanced technologies, the working noise of IBM Longteng fourth-generation hard disk is only 3. 1 bell (3 disks) to 3.0 bell (2 disks or less).

Hydrodynamic bearing technology: This technology is applied to the Deskstar 1 80Xp series hard disks released by IBM on June 65438+ 10/day, 2002, which is the same as Seagate's SoftSonic liquid bearing technology and can greatly reduce the noise of hard disks.

Automatic acoustic management: this technology is similar to the silent storage technology of Maituo Company, which reduces the noise by reducing the seek speed of hard disk. However, the tool IBM Feature Tool provided by IBM, compared with the sound management tool of Maituo, is not only gorgeous in interface, but also powerful in function. This is a toolkit, including sound management tools. Through the sound management tool, the hard disk can be switched back and forth in two working modes, one is the quiet seek mode with low noise, and the other is the normal seek mode with high performance. Noise is greatly reduced by slightly reducing the performance of the hard disk.

(4) Samsung noise reduction technology

For Samsung hard disk, some users may not be very clear. By the end of 1999, Samsung's hard disk production capacity reached120,000 pieces per month, but at that time it was mainly supplied to the market in the form of OEM, so Samsung's hard disk products rarely appeared in DIY market. However, as early as then, Samsung's hard disk set up the product characteristics of high performance, low noise and low working temperature, and enjoyed a good reputation in the industry. At present, Samsung's hard drives have entered the China market in a big way, mainly divided into V series with 5400 rpm and P series with 7200 rpm. These two series of hard disks adopt Samsung's unique hard disk noise reduction technology, and the mute effect is quite remarkable.

Noise guardian: It mainly includes three aspects. First, the sound insulation sheet is installed on the top cover to further prevent the internal vibration from spreading. Secondly, the design and structure of the top cover are improved to reduce the noise generated by the spindle motor. Finally, the design of spindle motor is improved to reduce the vibration caused by high-speed operation.

Silent seek: The principle of this technology is to optimize and fine-tune the driving waveform of the voice coil motor through a special DSP (Digital Signal Processor) to smooth the acceleration of the head arm during seek, and reduce the seek noise of the voice coil motor while ensuring the seek speed as far as possible.

4 computer hard disk noise reduction strategy (4)

Another method is to mute the hard disk.

(1) Set the automatic hibernation function of the hard disk, such as selecting the appropriate hard disk shutdown time through the BIOS power management setting option or setting the appropriate hard disk shutdown time in the WINDOWS power management option. If the system does not access the hard disk within the selected time, the hard disk motor will automatically stop running. Generally speaking, this method is not practical. First of all, it can't eliminate the harsh noise caused by head seek when reading and writing files continuously. Secondly, the hard disk is powered on and the number of times the head starts and stops is limited. In the early days, the trouble-free working time of hard disk was about 300,000 hours, while the number of times the head started and stopped was only1-30,000 times. The upper limit of the latest IDE hard disk head started and stopped was only 654.38+10,000 times. Frequent hard disk hibernation not only affects the continuous working speed of the system, but also shortens the physical life of the hard disk.

(2) The latest overall design

Because there are too many noise sources in the computer, it is difficult to completely solve them by one or two methods, so some people have put forward the design of "cabinet-type" and "split-type" computers, that is, putting the main chassis of the computer in the cabinet with the front panel closed or in another room to make it "invisible, inaudible and trouble-free". Theoretically, this method works best, but it must have a long signal line, and it is not convenient for you to switch CDs or floppy disks frequently.

(3) Hardware transformation

If you want to keep your ears quiet, try to choose those drive brackets with thick shells, no big openings, good fixity and low noise of power fans, such as Patriot's "Moonlight Box" series.

If you have to choose those cheap cases because of lack of money, you can also do some remedial measures. For example, you can pad some soft cloth at the bottom of the chassis; Tighten the screws on the chassis and add soft washers; The interior of the box body is lined with sound-absorbing materials such as foam plastic board; Changing the placement position of the chassis can also get good results. It's just that most of those sound-absorbing materials have poor thermal conductivity, so we should pay attention to the problem of ventilation and heat dissipation.