HOME

TheInfoList



OR:

A quiet, silent or fanless PC is a
personal computer A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or te ...
that makes very little or no
noise Noise is unwanted sound considered unpleasant, loud or disruptive to hearing. From a physics standpoint, there is no distinction between noise and desired sound, as both are vibrations through a medium, such as air or water. The difference aris ...
. Common uses for quiet PCs include video editing, sound mixing and
home theater PC A home theater PC (HTPC) or media center computer is a technological convergence, convergent device that combines some or all the capabilities of a personal computer with a software application that focuses on video, photo, audio playback, and ...
s, but noise reduction techniques can also be used to greatly reduce the noise from servers. There is currently no standard definition for a "quiet PC", and the term is generally not used in a business context, but by individuals and the businesses catering to them. A proposed general definition is that the sound emitted by such PCs should not exceed 30 dBA, but in addition to the average
sound pressure level Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average or equilibrium) atmospheric pressure, caused by a sound wave. In air, sound pressure can be measured using a microphone, and in water with a hydropho ...
, the frequency spectrum and dynamics of the sound are important in determining if the sound of the computer is noticed. Sounds with a smooth frequency spectrum (lacking audible tonal peaks), and little temporal variation are less likely to be noticed. The character and amount of other noise in the environment also affects how much sound will be noticed or masked, so a computer may be quiet with relation to a particular environment or set of users.


History

Prior to about 1975, all computers were typically large industrial/commercial machines, often in a centralized location with a dedicated room-sized cooling system. For these systems noise was not an important issue. The first home computers, such as the
Commodore 64 The Commodore 64, also known as the C64, is an 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in the Guinness W ...
, were very low power, and therefore could run fanless or, like the
IBM PC The IBM Personal Computer (model 5150, commonly known as the IBM PC) is the first microcomputer released in the IBM PC model line and the basis for the IBM PC compatible de facto standard. Released on August 12, 1981, it was created by a team ...
, with a low-speed fan only used to cool the power supply, so noise was seldom an issue. By the mid 1990s as CPU clock speeds increased above 60 MHz, "spot-cooling" was added by means of a fan over the CPU heatsink to blow air onto the processor. Over time, more fans were included to provide spot-cooling in more locations where heat dissipation was needed, including the 3D graphics cards as they grew more powerful. Computer cases increasingly needed to add fans to extract heated air from the case, but unless very carefully designed, this would add more noise.
Energy Star Energy Star (trademarked ''ENERGY STAR'') is a program run by the U.S. Environmental Protection Agency (EPA) and U.S. Department of Energy (DOE) that promotes energy efficiency. The program provides information on the energy consumption of pr ...
, in 1992, and similar programs led to the widespread adoption of sleep mode among consumer electronics, and the TCO Certified program promoted lower energy consumption. Both added features that allowed systems to only consume as much power as is needed at a particular moment and helped reduce power consumption. In a similar manner the first low power and energy-conserving CPUs were developed for use in laptops but can be used in any machine to reduce power requirements, and hence noise.


Causes of noise

The main causes of PC noise are: * Mechanical friction generated by disk drives and fan bearings * Vibration from disk drives and fans * Air turbulence caused by obstructions in the flow of air * Air vortex effects from fan blade edges * Electrical whine: noise generated by electrical coils or transformers used in power supplies,
motherboard A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expand ...
s,
video cards A graphics card (also called a video card, display card, graphics adapter, VGA card/VGA, video adapter, display adapter, or mistakenly GPU) is an expansion card which generates a feed of output images to a display device, such as a computer mo ...
or LCD monitors. Many of these sources increase with the power of the computer. More or faster transistors use more power, which releases more heat. Increasing the rotation speed of fans to address this will (all things being equal) increase their noise. Similarly, increasing
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 mag ...
s' and
optical disc drive In computing, an optical disc drive is a disc drive that uses laser light or electromagnetic waves within or near the visible light spectrum as part of the process of reading or writing data to or from optical discs. Some drives can only r ...
s' rotation speeds increases
performance A performance is an act of staging or presenting a play, concert, or other form of entertainment. It is also defined as the action or process of carrying out or accomplishing an action, task, or function. Management science In the work place ...
, but generally also vibration and bearing friction.


Measuring noise

Though standards do exist for measuring and reporting sound power output by such things as computer components, they are often ignored. Many manufacturers do not give sound power measurements. Some report sound pressure measurements, but those that do often do not specify how sound pressure measurements were taken. Even such basic information as measurement distance is rarely reported. Without knowing how it was measured, it is not possible to verify these claims, and comparisons between such measurements (e.g. for product selection) are meaningless. Comparative reviews, which test several devices under the same conditions, are more useful, but even then, an average sound pressure level is only one factor in determining which components will be perceived as quieter.


Noise reduction methods


Common noise reduction methods

* Use large, efficient
heat sink A heat sink (also commonly spelled heatsink) is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant, where it is dissipated away from the device, ...
s * Incorporate heat pipes, which have much higher effective thermal conductivity than solid copper * Use fans with lower speeds and larger diameters * Use fans with low bearing and motor noise * Rather than constant-speed fans, use thermostatically controlled variable speed fans that run at less than maximum speed, and thus run quieter most of the time * Use an efficient
power supply A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, current, and frequency to power the load. As ...
to minimize
waste heat Waste heat is heat that is produced by a machine, or other process that uses energy, as a byproduct of doing work. All such processes give off some waste heat as a fundamental result of the laws of thermodynamics. Waste heat has lower utilit ...
* Use quieter models of hard drive * Use solid state devices like
compact flash CompactFlash (CF) is a flash memory mass storage device used mainly in portable electronic devices. The format was specified and the devices were first manufactured by SanDisk in 1994. CompactFlash became one of the most successful of the e ...
or solid-state drives rather than traditional mechanical hard drives * Use remote networked via SMB or NFS rather than local disks * Place a damping material such as
Sorbothane Sorbothane is the brand name of a synthetic viscoelastic urethane polymer used as a shock absorber and vibration damper. It is manufactured by Sorbothane, Inc., based in Kent, Ohio. History Sorbothane was invented and patented in 1982 by Dr. Ma ...
around hard drives or other spinning items * Use
sound insulation Soundproofing is any means of impeding sound propagation. There are several basic approaches to reducing sound: increasing the distance between source and receiver, decoupling, using noise barriers to reflect or absorb the energy of the sound w ...
material to absorb sound and dampen case resonance *
Water cooling Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and non ...
, although difficult to set up, may be useful in some situations


Low-cost methods

A number of methods exist for reducing computer noise at little or no added cost. * Reduce CPU supply voltage ("undervolting"). Many of today's CPUs can run stably at their stock speed, or even with a slight overclock, at a reduced voltage, which reduces heat output. Power consumption is approximately proportional to ''V2·f'', that is, it varies linearly with the clock frequency and quadratically with the voltage. This means that even a small reduction in voltage can have a large effect in power consumption. Undervolting and underclocking can also be used with chipsets and GPUs. * Enable Cool'n'Quiet for AMD CPUs or
SpeedStep Enhanced SpeedStep is a series of dynamic frequency scaling technologies (codenamed Geyserville and including SpeedStep, SpeedStep II, and SpeedStep III) built into some Intel microprocessors that allow the clock speed of the processor to be dyna ...
(also known as EIST) on
Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 ser ...
CPUs. * Reduce fan speed. For newer computers, the speed of fans can be varied automatically, depending on how hot certain parts of the computer get. Lowering a DC fan motor's supply voltage will reduce its speed while making it quieter and lowering the amount of air the fan moves. Doing this arbitrarily could lead to components overheating; therefore, whenever performing hardware work it is advised to monitor the temperature of system components. Fans with
Molex Molex LLC is a manufacturer of electronic, electrical, and fiber optic connectivity systems. Molex offers over 100,000 products across a variety of industries, including data communications, medical, industrial, automotive and consumer electroni ...
connectors can be modified easily. With 3-pin fans, either fixed inline
resistor A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active e ...
s or
diode A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance); it has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other. A diod ...
s, or commercial fan controllers, such as the Zalman Fanmate, can be used. Software like speedfan or Argus Monitor may allow fan speed control. Many newer motherboards support
pulse-width modulation Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a method of reducing the average power delivered by an electrical signal, by effectively chopping it up into discrete parts. The average value of voltage (and current) fed ...
(PWM) control, allowing the fan speed to be set in the
BIOS In computing, BIOS (, ; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the b ...
or with software. * Mount fans on anti-vibration mounts. * Remove restrictive fan grills to allow easier airflow, or replace noisy fan grills with quieter versions. * Use software such as
Nero Nero Claudius Caesar Augustus Germanicus ( ; born Lucius Domitius Ahenobarbus; 15 December AD 37 – 9 June AD 68), was the fifth Roman emperor and final emperor of the Julio-Claudian dynasty, reigning from AD 54 un ...
''DriveSpeed'' or ''RimhillEx'' to reduce the speed of optical drives. * Isolate hard disk noise, either by using anti-vibration mounts (generally rubber or silicone grommets), or by suspending the hard disk to fully decouple it from the computer chassis by mounting it in a 5.25 inch
drive bay A drive bay is a standard-sized area for adding hardware to a computer. Most drive bays are fixed to the inside of a case, but some can be removed. Over the years since the introduction of the IBM PC, it and its compatibles have had many form f ...
with viscoelastic polymer mounts. * Set the hard disk's AAM value to its lowest setting. This reduces the seek noise produced by the hard drive, but also reduces performance slightly. * Set operating system to spin down hard drives after a short time of inactivity. This may reduce a drive's life span and commonly conflicts with the OS and running programs, though it can still be useful for drives that are only used for data storage. * Defragment hard drives to reduce the drive heads' need to search widely for data. This can also improve performance. * Arrange components and cables to improve airflow. Wires hanging inside the computer can block the airflow, which can increase the temperature. They can be easily moved to the side of the case so that air can pass through more easily. * Remove dust from inside the computer. Dust on computer parts will retain more heat. Fans draw in dust along with outside air; it can build up quickly inside the computer. Dust can be removed with a vacuum cleaner,
gas duster A gas duster, also known as canned air or compressed air, is a product used for cleaning or dusting electronic equipment and other sensitive devices that cannot be cleaned using water. This type of product is most often packaged as a can that, ...
, or compressed air. Special anti-static vacuum cleaners should be used, however, to prevent
electrostatic discharge Electrostatic discharge (ESD) is a sudden and momentary flow of electric current between two electrically charged objects caused by contact, an electrical short or dielectric breakdown. A buildup of static electricity can be caused by tribochar ...
(ESD). Ideally, this would be done often enough to prevent a significant amount of dust from ever building up. How frequently this would need to be performed would depend entirely on the environment in which the computer is used. In some cases an acceptable solution may be to relocate the too-noisy computer outside the immediate working area, and access it either with long-distance HDMI/USB/DVI cables or via remote desktop software from a quiet
thin client In computer networking, a thin client is a simple (low-performance) computer that has been optimized for establishing a remote connection with a server-based computing environment. They are sometimes known as ''network computers'', or in th ...
, e.g. based on a
Raspberry Pi Raspberry Pi () is a series of small single-board computers (SBCs) developed in the United Kingdom by the Raspberry Pi Foundation in association with Broadcom. The Raspberry Pi project originally leaned towards the promotion of teaching basic ...
, a miniature computer that does not even use a heat sink.


Individual components in a quiet PC

The following are notes regarding individual components in quiet PCs. The motherboard, CPU, and video card are major energy users in a computer. Components that need less power will be easier to cool quietly. A quiet power supply is selected to be efficient while providing enough power for the computer.


Motherboard

A motherboard based on a chipset that uses less energy will be easier to cool quietly.
Undervolting Dynamic voltage scaling is a power management technique in computer architecture, where the voltage used in a component is increased or decreased, depending upon circumstances. Dynamic voltage scaling to increase voltage is known as overvolting; ...
and
underclocking Underclocking, also known as downclocking, is modifying a computer or electronic circuit's timing settings to run at a lower clock rate than is specified. Underclocking is used to reduce a computer's power consumption, increase battery life, red ...
generally require motherboard support, but when available can be used to reduce energy use and heat output, and therefore cooling requirements. Many modern motherboard chipsets have hot northbridges which may come with active cooling in the form of a small, noisy fan. Some motherboard manufacturers have replaced these fans by incorporating large heat sinks or heatpipe coolers, however they still require good case airflow to remove heat. Motherboard
voltage regulator A voltage regulator is a system designed to automatically maintain a constant voltage. A voltage regulator may use a simple feed-forward design or may include negative feedback. It may use an electromechanical mechanism, or electronic components ...
s also often have heat sinks and may need airflow to ensure adequate cooling. Some motherboards can control the fan speed using an integrated hardware monitoring chip (often a function within a
Super I/O Super I/O is a class of I/O controller integrated circuits that began to be used on personal computer motherboards in the late 1980s, originally as add-in cards, later embedded on the motherboards. A super I/O chip combines interfaces for a vari ...
solution), which can be configured through
BIOS In computing, BIOS (, ; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the b ...
or with a system monitoring software like SpeedFan and Argus Monitor, and most recent motherboards have built-in PWM fan control for one or two fans. Even though a given hardware monitoring chip may be capable of performing fan control, a motherboard manufacturer may not necessarily wire up the fan header pins of the motherboard correctly to the hardware monitoring chip, thus sometimes
computer fan control A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These prog ...
cannot be performed on a given motherboard due to the wiring irregularities, even though the software may indicate that the fan control is available due to the underlying support by the hardware monitoring chip itself. Other times, it may be the case that a single fan-control setting may affect all fan connector headers on the motherboard at the same time, even if individual settings for each fan are available in the hardware monitoring chip itself; these wiring issues being very common makes it difficult to design good general-purpose
user interface In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine f ...
s for configuring fan control. Motherboards can also produce audible electromagnetic noise.


CPU

The heat output of a CPU can vary according to its brand and model or, more precisely, its thermal design power (TDP).
Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 ser ...
's third revision Pentium 4, using the "Prescott" core, was infamous for being one of the hottest-running CPUs on the market. By comparison, AMD's
Athlon Athlon is the brand name applied to a series of x86-compatible microprocessors designed and manufactured by Advanced Micro Devices (AMD). The original Athlon (now called Athlon Classic) was the first seventh-generation x86 processor and the fi ...
series and the Intel Core 2 perform better at lower clock speeds, and thus produce less heat. Modern CPUs often incorporate energy saving systems, such as Cool'n'Quiet,
LongHaul VIA LongHaul is a CPU speed throttling and power saving technology developed by VIA Technologies. By executing specialized instructions, software can exercise fine control on the bus-to-core frequency ratio and CPU core voltage. When the s ...
, and
SpeedStep Enhanced SpeedStep is a series of dynamic frequency scaling technologies (codenamed Geyserville and including SpeedStep, SpeedStep II, and SpeedStep III) built into some Intel microprocessors that allow the clock speed of the processor to be dyna ...
. These reduce the CPU clock speed and core voltage when the processor is idle, thus reducing heat. The heat produced by CPUs can be further reduced by
undervolting Dynamic voltage scaling is a power management technique in computer architecture, where the voltage used in a component is increased or decreased, depending upon circumstances. Dynamic voltage scaling to increase voltage is known as overvolting; ...
,
underclocking Underclocking, also known as downclocking, is modifying a computer or electronic circuit's timing settings to run at a lower clock rate than is specified. Underclocking is used to reduce a computer's power consumption, increase battery life, red ...
or both. Most modern mainstream and value CPUs are made with a lower TDP to reduce heat, noise, and power consumption. Intel's dual-core
Celeron Celeron is Intel's brand name for low-end IA-32 and x86-64 computer microprocessor models targeted at low-cost personal computers. Celeron processors are compatible with IA-32 software. They typically offer less performance per clock speed co ...
,
Pentium Pentium is a brand used for a series of x86 architecture-compatible microprocessors produced by Intel. The original Pentium processor from which the brand took its name was first released on March 22, 1993. After that, the Pentium II and P ...
, and i3 CPUs generally have a TDP of 35–54 W, while the i5 and i7 are generally 64–84 W (newer versions, such as Haswell) or 95W (older versions, such as Sandy Bridge). Older CPUs such as the Core 2 Duo typically had a TDP of 65 W, while the Core 2 Quad CPUs were mostly 65–95 W. AMD's Athlon II x2 CPUs were 65 W, while the Athlon x4 was 95 W. The
AMD Phenom Phenom is the 64-bit AMD desktop processor line based on the K10 microarchitecture, in what AMD calls family 10h (10 hex, i.e. 16 in normal decimal numbers) processors, sometimes incorrectly called "K10h". Triple-core versions (codenamed ''T ...
ranged from 80 W in the x2 variant to 95 and 125 W in the quad-core variants. The
AMD Bulldozer The AMD Bulldozer Family 15h is a microprocessor microarchitecture for the FX and Opteron line of processors, developed by AMD for the desktop and server markets. Bulldozer is the codename for this family of microarchitectures. It was released ...
CPUs range from 95–125 W. The
APUs Apus is a small constellation in the southern sky. It represents a bird-of-paradise, and its name means "without feet" in Greek because the bird-of-paradise was once wrongly believed to lack feet. First depicted on a celestial globe by Pet ...
range from 65 W for the lower-end dual-core variants, such as the A4, to 100 W in the higher-end quad-core variants, such as the A8. Some processors come in special low power versions. For example, Intel's lower TDP CPUs end in T (35 W) or S (65 W).


Video card

Video card A graphics card (also called a video card, display card, graphics adapter, VGA card/VGA, video adapter, display adapter, or mistakenly GPU) is an expansion card which generates a feed of output images to a display device, such as a computer m ...
can produce a significant amount of heat. A fast
GPU A graphics processing unit (GPU) is a specialized electronic circuit designed to manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display device. GPUs are used in embedded systems, mobi ...
may be the largest power consumer in a computer and because of space limitations, video card coolers often use small fans running at high speeds, making them noisy. Options to reduce noise from this source include: * Replace the stock
cooler A cooler, portable ice chest, ice box, cool box, chilly bin (in New Zealand), or esky ( Australia) is an insulated box used to keep food or drink cool. Ice cubes are most commonly placed in it to help the contents inside stay cool. Ice packs a ...
with an aftermarket one. * Use motherboard video output. Typically, motherboard video takes less power, but provides lower gaming or HD video decoding performance. * Select a video card that does not use a fan. * Most modern graphics cards come with tools that allow the user to reduce the power target and adjust fan curves, resulting in quieter operation at a cost of performance


Power supply

Power supply A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, current, and frequency to power the load. As ...
(PSU) is made quieter through the use of higher efficiency (which reduces waste heat and need for airflow), quieter fans, more intelligent fan controllers (ones for which the correlation between temperature and fan speed is more complex than linear), more effective heat sinks, and designs that allow air to flow through with less resistance. For a given power supply size, more efficient supplies such as those certified 80 plus generate less heat. A power supply of appropriate wattage for the computer is important for high efficiency and minimizing heat. Power supplies are typically less efficient when lightly or heavily loaded. High wattage power supplies will typically be less efficient when lightly loaded, for instance when the computer is idle or sleeping. Most desktop computers spend most of their time lightly loaded. For example, most desktop PCs draw less than 250 watts at full load, and 200 watts or less is more typical. Power supplies with thermally controlled fans can be made quieter by providing a cooler and/or less obstructed source of air, and fanless power supplies are available, either with large passive heat sinks or relying on convection or case airflow to dissipate heat. It is also possible to use fanless DC to DC power supplies that operate like those in laptops, using an external power brick to supply DC power, which is then converted to appropriate voltages and regulated for use by the computer. These power supplies usually have lower wattage ratings. The electrical coils in power supplies can produce audible electromagnetic noise which can become noticeable in a quiet PC. Equipping the PSU with a power cord that uses a ferrite bead can sometimes help to reduce humming from the PSU.


Case

Case designed for low noise usually include quiet fans, and often come with a quiet power supply. Some incorporate heatsinks to cool components passively. Larger cases provide more space for airflow, larger coolers and heat sinks, and sound dampening material.


Airflow

Noise-optimized cases often have ducting and partitioning within the case to optimize airflow and to thermally isolate components. Vents and ducts may easily be added to regular cases. Case designed to be quiet typically have wire grills or honeycombed fan grills. Both are far superior to the older style of stamped grill. Features that facilitate neat cable management, such as brackets and space to run cables behind the motherboard tray, help increase cooling efficiency. Air filters can help to prevent dust from coating heat sinks and surfaces, which dust impedes heat transfer, making fans spin faster. However, the filter itself can increase noise if it restricts airflow too much or is not kept clean, requiring a larger or faster fan to handle the pressure drop behind the filter.


Soundproofing

The inside of a case can be lined with dampening materials to reduce noise by: * attenuating the vibration of the case panels via extensional damping or constrained-layer damping * reducing the amplitude of the vibration of the case panels by increasing their mass * absorbing airborne noise, such as with foam


Cooling systems


Heat sink

Large heat sink designed to operate efficiently with little airflow are often used in quiet computers. Often heat pipes are used to more efficiently distribute heat to the heat sink.


Fan

If they use fans at all, quiet PCs typically use larger-than-usual low-speed fans with quiet-running motors and bearings. The 120 mm size is common, and 140 mm fans are used where cases or heat sinks allow them. Quiet fan manufacturers include Nexus, EBM-Papst, Yate Loon, Scythe, and Noctua. Extensive comparative surveys have been posted by SPCR and MadShrimps. Fan noise is often proportional to fan speed, so fan controllers can be used to slow down fans and to precisely choose fan speed. Fan controllers can produce a fixed fan speed using an inline resistor or diode; or a variable speed using a
potentiometer A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat. The measuring instrum ...
to supply a lower voltage. Fan speed can also be reduced more crudely by plugging them into the power supply's 5 volt line instead of the 12 volt line (or between the two for a potential difference of 7 volts, although this cripples the fan's speed sensing). Most fans will run at 5 volts once they are spinning, but may not start reliably at less than 7 V. Some simple fan controllers will only vary the fans' supply voltage between 8 V and 12 V to avoid this problem entirely. Some fan controllers start the fan at 12 V, then drop the voltage after a few seconds. PWM fan control, however, is the easiest and most efficient option for modern motherboards that have PWM fan headers.
PWM fan PWM may refer to: Science and technology * Position weight matrix, a representation in motifs in biological sequences * Pulse-width modulation, a technique for controlling the average power delivered by an electrical signal * PWM (window manager ...
control rapidly cycles between feeding the fan full voltage and no voltage, to control rotational speed. Typically the motherboard chipset provides temperature data from sensors on the CPU itself to control speed. Bearing and motor noise is an important consideration. Soft mounting fans (e.g. with rubber or silicone fan isolators) can help reduce transfer of fan vibration to other components. Piezoelectric fans are often quieter than rotating fans and may consume less power. Intel, Murata, and others have recently done development on use of piezoelectric fans in desktop PCs.


Watercooling

Watercooling is a method of heat-dissipation by transferring the heat through a conductive material which is in contact with a liquid, such as demineralised water with an additive to prevent bacterial growth. This water travels in a loop that usually contains a reservoir, radiator and pump. Modern 12 V DC pump technologies allow extremely powerful and quiet designs. By efficiently transferring device heat to a separate heat exchanger that can use larger heat sinks or fans, watercooling can allow quieter overall operation. Devices such as GPUs, Northbridges, Southbridges,
hard disk drives 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 magn ...
,
memory Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remember ...
,
voltage regulator module A voltage regulator module (VRM), sometimes called processor power module (PPM), is a buck converter that provides microprocessor and chipset the appropriate supply voltage, converting , or to lower voltages required by the devices, allowing dev ...
s (VRMs), and even power supplies can be separately watercooled; in fact the whole PC can be immersed, in some cases.


Secondary storage


Hard drive

Older hard drive used
ball bearing A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this ...
motors but more recent desktop hard drives use quieter
fluid bearing Fluid bearings are bearings in which the load is supported by a thin layer of rapidly moving pressurized liquid or gas between the bearing surfaces. Since there is no contact between the moving parts, there is no sliding friction, allowing flu ...
motors. The smaller 2.5" form-factor hard drives generally vibrate less, are quieter, and use less power than traditional 3.5" drives, but often have lower performance and less capacity, and cost more per
gigabyte The gigabyte () is a multiple of the unit byte for digital information. The prefix '' giga'' means 109 in the International System of Units (SI). Therefore, one gigabyte is one billion bytes. The unit symbol for the gigabyte is GB. This definit ...
. To minimize vibrations from a hard drive being transferred to, and amplified by, the case, hard drives can be mounted with soft rubber studs, suspended with elastics or placed on soft foam or
Sorbothane Sorbothane is the brand name of a synthetic viscoelastic urethane polymer used as a shock absorber and vibration damper. It is manufactured by Sorbothane, Inc., based in Kent, Ohio. History Sorbothane was invented and patented in 1982 by Dr. Ma ...
. Hard disk enclosures can also help reduce drive noise, but care must be taken to ensure that the drive gets adequate cooling - with disk temperatures often be monitored by SMART software.


Solid-state storage

A
solid-state drive A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is a ...
has no moving mechanical components and runs silently, STEC
SSD Power Savings Render Significant Reduction to TCO
." Retrieved October 25, 2010.
but () are still roughly four times more expensive per unit of storage than consumer-grade HDDs. In some cases, other solid state storage methods may be suitable: *
Compact Flash CompactFlash (CF) is a flash memory mass storage device used mainly in portable electronic devices. The format was specified and the devices were first manufactured by SanDisk in 1994. CompactFlash became one of the most successful of the e ...
(CF) cards can be used as secondary storage. Because they use a slightly modified
Parallel ATA 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 connect ...
(PATA) interface, a simple adapter is all that is needed to connect CF cards to function as an PATA or
PC Card In computing, PC Card is a configuration for computer parallel communication peripheral interface, designed for laptop computers. Originally introduced as PCMCIA, the PC Card standard as well as its successors like CardBus were defined and devel ...
hard disk. CF cards are also small, allowing SFF PCs to be made, produce no noise, use very little power (further reducing heat output in the AC/DC conversion in the PSU), and an insignificant amount of heat. However, they are very expensive per GB and are only available in small capacities and there are also issues regarding the maximum number of writes to each sector. *
USB flash drives A USB flash drive (also called a thumb drive) is a data storage device that includes flash memory with an integrated USB interface. It is typically removable, rewritable and much smaller than an optical disc. Most weigh less than . Since first ...
can be used if a motherboard supports booting from USB. They are based on
flash memory Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both use ...
, so have the same advantages and disadvantages as CF cards, except that speed is limited by the USB bus. *
i-RAM The i-RAM is a solid-state storage device produced by Gigabyte and released in June 2005. It has four DDR RAM DIMM slots, and a connection via a SATA port enables a PC to see the i-RAM as a hard disk drive, which can also be made bootable. Th ...
is a solid-state disk which has four DIMM slots to allow regular PC
RAM Ram, ram, or RAM may refer to: Animals * A male sheep * Ram cichlid, a freshwater tropical fish People * Ram (given name) * Ram (surname) * Ram (director) (Ramsubramaniam), an Indian Tamil film director * RAM (musician) (born 1974), Dutch * ...
to be used like a disk. It is much faster than a hard disk, does not have the write cycle limitations of flash memory, however it requires power continuously in order to maintain its contents (from standby power or a battery when the system is off), uses more power than many laptop hard drives, has maximum capacity of 4 GiB, and is expensive. All forms of solid-state storage are more expensive than traditional spinning-disk drives, so some quiet PC designs use them in conjunction with a secondary hard drive which is only accessed when needed, or with
network-attached storage Network-attached storage (NAS) is a file-level (as opposed to block-level storage) computer data storage server connected to a computer network providing data access to a heterogeneous group of clients. The term "NAS" can refer to both the tech ...
, where less-quiet traditional hard drives are kept remote.


Optical drive

Optical drives can be slowed down by software to quiet them, such as
Nero Nero Claudius Caesar Augustus Germanicus ( ; born Lucius Domitius Ahenobarbus; 15 December AD 37 – 9 June AD 68), was the fifth Roman emperor and final emperor of the Julio-Claudian dynasty, reigning from AD 54 un ...
DriveSpeed, or emulated by virtual drive programs such as
Daemon Tools DAEMON Tools is a virtual drive and optical disc authoring program for Microsoft Windows and Mac OS. Overview DAEMON tools was originally a successor of ''Generic SafeDisc emulator'' and incorporated all of its features. The program claims ...
to eliminate their noise entirely. Notebook optical drives can be used, which tend to be quieter, however this may be because they tend to run slower (typically 24× CD speed, 8× DVD speed). Some DVD drives have a feature, commonly called Riplock, which reduces drive noise by slowing the drive during video playback. For playback operations only 1x (or real time) speed is required.


External components


Monitor

A CRT monitor can produce coil noise, as can the external power supply for an LCD monitor or the voltage converter for the monitor's backlight. LCD monitors tend to produce the least noise (whine) when at full brightness. Reducing brightness using the video card does not introduce whine, but may reduce color accuracy. An LCD monitor with an external power supply tucked out of the way will produce less noticeable noise than one with the power supply built into the screen housing.


Printer

In the past, particularly noisy printers such as
dot matrix A dot matrix is a 2-dimensional patterned array, used to represent characters, symbols and images. Most types of modern technology use dot matrices for display of information, including mobile phones, televisions, and printers. The system is al ...
and daisy wheel designs were often housed in soundproofed boxes or cabinets, and the same technique can be used with modern printers to reduce their perceived noise. Another solution is to network the printer, and locate it physically away from the immediate work area.


Laptop

In contrast to desktop PCs, laptops and notebooks typically do not have power supply fans or video card fans, generally use physically smaller hard drives and lower-power components. However, laptop CPU fans are usually smaller, so may not necessarily be quieter than their desktop counterparts - a smaller fan area requires faster fan speeds to move the same amount of air. Furthermore, limited space, limited access and proprietary components make silencing them more difficult.


Fanless

A number of laptops and netbooks however do not use cooling fans at all. Fanless
portable computer A portable computer is a computer designed to be easily moved from one place to another and included a display and keyboard together, with a single plug, much like later desktop computers called '' all-in-ones'' (AIO), that integrate the s ...
s ( tablet pcs,
subnotebook Subnotebook, also called ultraportable, superportable, or mini notebook, was a marketing term for laptop computers that are smaller and lighter than a typical notebook-sized laptop. Types and sizes As typical laptop sizes have decreased over t ...
s,
chromebook A Chromebook (sometimes stylized in lowercase as chromebook) is a laptop or tablet running the Linux-based ChromeOS as its operating system. Initially designed to heavily rely on web applications for tasks using the Google Chrome browser, Chrome ...
s,
ultrabook Ultrabook is a marketing term, originated and trademarked by Intel, for a category of high-end laptop computers. They were originally marketed as featuring ultra thin form factor and light weight design without compromising battery life or per ...
s and
2-in-1 PC A 2-in-1 PC, also known as convertible laptop, 2-in-1 tablet, 2-in-1 laptop, 2-in-1 detachable, laplet, tabtop, laptop tablet, or simply 2-in-1, is a portable computer that has features of both tablets and laptops. Before the emergence of ''2- ...
s) running under 10-15 W on
mobile CPU A mobile processor is found in mobile computers and cellphones. A CPU chip is designed for portable computers to run fanless, under 10-15W, which is cool enough without a fan. It is typically housed in a smaller chip package, but more importan ...
s (most commonly
ARM processor ARM (stylised in lowercase as arm, formerly an acronym for Advanced RISC Machines and originally Acorn RISC Machine) is a family of reduced instruction set computer (RISC) instruction set architectures for computer processors, configured ...
s) became popular after
netbook Netbook was a commonly used term that identified a product class of small and inexpensive laptops which were sold from 2007 to around 2013. These machines were designed primarily as cost-effective tools for consumers to access the Inte ...
s but then mainly after the introduction of the first
iPad The iPad is a brand of iOS and iPadOS-based tablet computers that are developed by Apple Inc., Apple Inc. The iPad was conceived before the related iPhone but the iPhone was developed and released first. Speculation about the development, ...
in 2010. The first iPad's CPU, the ARM Cortex-A8 was the first Cortex design to be adopted on a large scale in consumer devices.


References


External links

* – articles on various aspects of PC acoustics. ** . ** . ** . ** . * . {{DEFAULTSORT:Quiet Pc Personal computers Computers and the environment Noise pollution