How to Build a Quiet PC? A Simple Guide
By Dr.Necro
There are several good reasons to have your PC as quiet as possible. For instance, you may use your PC in a music studio and you don't want your microphone to pick up the noise from your PC. You may have your PC in a bedroom where you don't want to have it bothering you or your roommate's sleep while you keep it on all the time. Your PC may be the only source of annoying noises in an otherwise quiet office. You would not like the noise if you work in a hospital, library, or other jobs where "QUIET" sign is often posted in big letters. High noise level could be a source for stress and low-productivity.
Source of the Noise. A typical PC may generate 36-45dB(A) noise level. 33-36dB(A) is considered low noise level. Below 33dB(A) is considered quiet. Below 28dB(A) is considered silent.
There are five basic sources of noise from a PC:
Cooling fan inside the power supply.
Cooling fan for the microprocessor.
Case fan(s).
Hard drive(s).
Drives such as floppy, CD-ROM, zip, DVD, and CDRW when they are in operation.
There are two ways to deal with the noises. One is to eliminate them. The other is to minimize them if you can't eliminate them. Here are some tips for both.
Noise Elimination.
Use a very large and efficient heat sink for the microprocessor with a small cooling fan or no fan at all.
Tighten the motherboard to the case to ensure that there is no noise amplification through resonance. Do not use plastic spacers. Always use metal screws.
Use a large (heavy) motherboard if possible.
Tighten the case fans to the case really well.
Tighten the case covers and panels to prevent any noise amplification through vibration.
Tighten hard drives and other drives to eliminate vibration through the case structure.
Use an aluminum case to dissipate heat without adding too many case fans.
Replace noisy drives.
Noise Minimization.
Use smaller case fans.
Use quiet case fans, typically with lower RPM and/or at lower voltage. Most case fans are designed with 12V DC power supply. By using a 12V to 7V adapter, one can actually provide 7V to a fan, making it running slower and much quieter.
Use case fans that adjust speed according to the temperature inside a case.
Use quiet CPU coolers. Typically running slower and/or at lower voltage. To compensate the lower speed, a fan-duct or air guard is recommended to keep the CPU cool.
Use enclosures for hard drives to muff the hard drives.
Use a sound damping liner inside the case.
Use sealing materials such as foam and rubber to seal off the case edges.
Change the fan inside the power supply to a quiet one or buy a quiet power supply. Quiet power supplies may have fans whose RPM changes with the temperature inside the case.
Choose quiet drives whenever possible.
Keep the CPU box in side a cabinet.
Use Grommets at key areas where transmission of vibration may cause noise, like in fan and drive mounts.
Precaution. Keeping a PC quiet is contradictory to keeping PC components cool. This is especially true in today's high-speed computers. While keeping them quiet, you may want to keep the components, especially the CPU, as cool as possible by passive heat-removing materials such as thermal compound and large heat sinks together with temperature monitoring devices to alert problems. The extra cooling fans cause more noise. We believe that keeping a PC cool should take priority over keeping a PC quiet. After all your PC may be deadly quiet if the CPU overheats!
