Quiet PC
Sounds with a smooth frequency spectrum (lacking audible tonal peaks), and little temporal variation are less likely to be noticed.
[1] Prior to about 1975, all computers were typically large industrial/commercial machines, often in a centralized location with a dedicated room-sized cooling system.
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.
Though standards do exist for measuring and reporting sound power output by such things as computer components, they are often ignored.
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.
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, e.g. based on a Raspberry Pi, a miniature computer that does not even use a heat sink.
Many modern motherboard chipsets have hot northbridges which may come with active cooling in the form of a small, noisy fan.
Motherboard voltage regulators also often have heat sinks and may need airflow to ensure adequate cooling.
The heat output of a CPU can vary according to its brand and model or, more precisely, its thermal design power (TDP).
By comparison, AMD's Athlon series and the Intel Core 2 perform better at lower clock speeds and thus produce less heat.
Most modern mainstream and value CPUs are made with a lower TDP to reduce heat, noise, and power consumption.
A fast GPU may be the largest power consumer in a computer[16] 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: Power supply (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.
High-wattage power supplies will typically be less efficient when lightly loaded, for instance when the computer is idle or sleeping.
[20] 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.
The electrical coils in power supplies can produce audible electromagnetic noise which can become noticeable in a quiet PC.
The inside of a case can be lined with dampening materials to reduce noise by: Large heat sinks designed to operate efficiently with little airflow are often used in quiet computers.
Quiet fan manufacturers include Nexus, EBM-Papst,[30] Yate Loon, Scythe,[31] and Noctua.
Typically the motherboard chipset provides temperature data from sensors on the CPU itself to control speed.
[40] Watercooling[41] is a method of heat-dissipation by transferring the heat through a conductive material which is in contact with a liquid, such as demineralized water with an additive to prevent bacterial growth.
Devices such as GPUs, Northbridges, Southbridges, hard disk drives, memory, voltage regulator modules (VRMs), and even power supplies can be separately watercooled;[42] in fact the whole PC can be immersed, in some cases.
A solid-state drive has no moving mechanical components and runs silently,[45][46][47][48] but (as of 2016[update]) are still roughly four times more expensive per unit of storage than consumer-grade HDDs.
[52][53][54][55][needs update] Fanless portable computers (tablet pcs, subnotebooks, chromebooks, ultrabooks and 2-in-1 PCs) running under 10-15 W[56] on mobile CPUs (most commonly ARM processors) became popular after netbooks but then mainly after the introduction of the first iPad 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.
