My first serious write-up; in progress but hopefully usable.
Also pardon my poor HTML, only a beginner.
Noise in a PC can be a permanent source of scorn, especially if you use a Computer all day. The situation is worsened
dramatically if the PC is in a very small room, somehow this makes it seem a lot louder. Noise levels from 40 dB
upwards can be considered as distracting / annoying, anything below 25 dB regarded as ideal.
To assess whether you have a noise problem simply shut down (unless its a server :) after working for about 1-2 hours. Listen. Breath out & relax. Wait for
2 minutes then turn it on again. How does that feel? You will know either on switching it on or (worse) when
switching it off whether your Computer has a noise problem.
Easy method:
Go to a website that specializes in silent PC cases (e.g. www.silentmaxx.de). Get a special insulated case, a Power
Supply Unit with silent fans and a quiet CPU cooler (e.g. Papst, Zalman). Or get a kit that supports watercooling.
Componentized Method:
You need this if you already have a PC and maybe just want to 'make it quieter' without starting from scratch.
In order to do this you first need to look at the main sources of noise in a PC. There are two main contributors:
- Air Flow (Fans)
- Mechanical movement (Disc Drives)
PSU (Power Supply unit) and CPU Cooling Fan are usually the worst offenders especially in standard PCs as they
tend to use cheap standard coolers.
Especially nowadays with highly clocked Processors cooling has to be excessive to be sufficient. AMD Athlon
Processors need more cooling compared to Intel P4, as they use more power, so this is one of the points to
watch out for, get a PSU with 350 Watts at least if you go for Athlon XP and make sure the CPU cooler is designed
for the particular type of processor (which includes processor speed). Instead of paying 5 $(US) expect to pay around
25 to 60 $ for the CPU cooling.
For fan types there is a plethora of models to choose from, some of them looking really exotic (e.g. the Zalman
Flower Heatsink, a lot of this is just pure design and more interesting for case mods with a window. (See
Tom's Hardware tests @ http://www.tomshardware.com/cpu/01q2/010521/ for comparisons) Apart from cooling enough and
being quiet, the unit should not be too heavy to sit on the CPU securely.
The other fans one should look at are (in order of noise significance) Graphics Adaptor Processor fan - if you need 3d
performance, chances are you have quite a heat generator on the graphics card. You could get an old 2d card or try and
replace the fan. Another option is to try and get a 3d accelerated card with a passive heatsink -
e.g. a VisionTek XTasy nVidia MX 440 card this one still gives acceptable 3d performance (I know hardcore gamers will
probably dispute this) but doesn't generate any noise (I picked this one because it has 2 VGA outputs which can be of
advantage, YMMV).
Lately there is a fashion with VGA cards to use unusually shaped or colored fans to set them apart from the
competition; strange if you think that only a very small minority puts a window in their case, so there is only a
limited aesthetic benefit.
Northbridge fan; this one is usually fairly small but may be replaced with something more quiet. In a
tower PC it is usually located on
the mainboard underneath the CPU (assuming the tower is standing).
Additional Airflow Measures
Lower noise with fans can be achieved by special geometry of the propeller and by having a temperature - controlled
fan, also by special geometry of the heatsink. It can also be achieved by optimizing the airflow in the PC. On
method is to have a separate air intake in the front of the PC, also a secondary fan on the bottom of the PSU. Also it
is considered advantageous to replace flat ribbon cables with rounded versions, which I would consider especially
true for small cases.
Another approach is to replace all fans and switch to water cooling. In the meantime there
are watercooling kits available that include a customized case, water pump and additional
fittings an idea that will soon make it into the mainstream. Or a cryogenic PC, which is more suitable for
overclock.
Quiet Drives
Noise from Hard drives can be quite annoying, here it not so much the loudness as the type of frequency that the
hard drive emits. Noises range from clicking (especially if the drive is fragmented), constant hum or vibration (can
be increased by transmitting into the case) and high pitched noises through high RPM. Some of these noises are
constant, others only occur after resuming from a sleep period (drive starts to spin, more annoying). A lot of current
drives operate at 10.000 rpm and above which can generate an annoying highpitched noise.
Highperformance drives can produce more heat so some of them might have in built fans (here we go again). Buying a
drive with 7200 RPM may be a solution if top end performance is not paramount. In cany case it is vital to read
reviews that mention the noise
Special silent drives (e.g. liquid bearing) can help, or if you already have the drive use silent drive enclosures. An
example for a not overly expensive hard drive that is near silent is the SeaGate ST 340016a (40gb).
Cd ROM drives and burners can be very annoying, the higher the multi-speed the worse. Remember that CDs were not
designed to run at 50 times the speed [that they were designed for], so selecting something a little slower (20*
instead of 50*) may help. On top you can restrict the speed of the CD drive by configuration or 3rd party software, of
course the tradeoff is performance. CDBremse is example for a utility designed to minimize noise from CD Rom drives.
Silent PC Cases
Although this an essential part in building a quiet PC, I am listing this after all the other components because it
will have less of a dramatic impact if you are using components that emit a lot of noise. In fact getting a specially
insulated case will buy you near to no noise relief if you have just one very noisy fan in the system. Such cases are
usually designed to further decrease the noise emitted by components that are already "noise aware".
Cases can be silenced by either using material (& thickness) that doesn't vibrate easily and / or glueing vibration
dampening multicomponent materials on the inside. These self adhesive silent kits can also be acquired separately if
you want to keep your original case. A good silent case would also have a door hiding the front with any removable
drives. Location of the case can of course also help, although if you have kids around your place you might not want
to have your tower under the desk. Poking out calling cards or salamis from a CD drive is not as entertaining as the
advertisements would have us believe, ahem.