Products available to control PC noise
Cases: There are some cases designed to be
quiet and marketed on that claim. Using a search engine for terms like
“quiet cases” or “totally no noise cases” should point you in the
right direction. Some of these cases are built like huge heat-sinks and
use clever technology that will allow you to dispense with the use of all
fans inside the PC, including processor, graphics card and other fans.
There are other cheaper cases marketed as quiet cases that have an acoustic
lining inside the case that absorbs some of the internal sounds. Either
way having a quality case makes a lot of difference. Case rattle is one of
the most common causes of PC noise (see section 1 above on “cheapest
ways to reduce noise”)
Acoustic lining: A variety of acoustic lining
products are available. Some of them are basic sheets of foam. Some are
dual layer products with a thicker barrier material under a layer of sound
absorbing foam. These lining products usually have self adhesive backing.
You can cut the sheets to fit along the inside of your case, peel the back
off and fit them yourself. Some acoustic lining
products are as little as
3-4 mm in thickness, others as much as 17 mm. If space is restricted in
your case you may want to go for the thinner (but less effective)
products. Things to note: There are some cheap bitumen based products that
degrade quickly over time and can be quite risky. Also, if your PC does
rely extensively on the case body to dissipate heat (as is common with
many aluminium cases) then you may want to create some additional airflow
to compensate for the reduced cooling. You can do this via extra chassis
fans. The blocks of foam in the picture fit into empty 5.25" and
3.5" drive bays to fill space that may otherwise be trapping hot air.
Using these foam blocks reduces the volume of air within the box resulting
in a faster "turnover" of air.
CPU (Processor) fans: A variety of specialist
fan manufacturers make low noise heat sink + fans combinations for processors. These involve using
copper contacts to better transfer heat from the processor to the heat
sink, using large heat sinks to quickly move the heat away from the CPU,
and using large, low noise fans to blow air over the heat sink. Under 30
dba is usually considered quiet for these fans. The problem with larger
heat sinks is that they don’t fit in all cases and they are particularly
not suited to low profile desktop cases so please do check the available
space above your processor before you buy one of these.
Water cooling: This has been gaining
popularity despite the obvious downsides of combining water and
As liquid absorbs and transfers heat more effectively than air does there is a practical
argument in favour of water cooling. How it works is that the specially
manufactured processor heat sink has two tubes connected to it. One feeds
liquid to the heat sink and the other takes the liquid back to the
external pump. Some cases manufacturers now provide the water cooling kits
as options with some of their cases. One or two manufacturers also provide
the water cooling kits integrated into some of their larger cases saving
you the unsightly mess of having a pump and tubes on your table top. In
either case though you will need to have an external "radiator"
unit that dispels the heat.
problem with water of course, is that unlike air cooled systems water
needs to be enclosed. And it needs to stay enclosed – with no leaks - or
it will damage the electronic components in your PC. This makes for
equipment that is both bulky and expensive.
Other Cooling: Peltier coolers and other heat
exchange systems have been tried in PCs with limited success. Issues like
condensation etc cause problems in peltier solutions. Also, peltier
coolers need your heat to be constant. If your PC isn't under constant,
even use and/or you have energy saving features that trigger
"sleep/suspension" modes or "CPU idling" you can't use
a Peltier refrigerator/cooler; that excludes most PCs. Thermoelectric
engineers have experimented with turning heat into electricity in a
variety of other ways but most methods require large amounts of heat - about
200-300 degrees C - and even then only about 20% of the heat is converted
to electricity. Other thermoelectric solutions consume a lot of power
and/or generate substantial heat themselves and require active cooling.
Hard Disks: Apart from the fans in a PC hard
disks are the only moving parts that are always moving (optical drives
only move when you have a DVD or CD in them). In 2004 it’s possible to
buy/build a PC without fans but you still can’t have one without a hard
disk (unless it’s a thin client on a network – but that’s another
story). And hard disks are usually noisy. Your data is stored on platters
on the disk and there are reading heads in the drive that write this data
to the platters and access/read the data when you need it. The spinning of
the drive causes the whining noise you get with hard disk. The head
moving about causes the trashing sound. Hard disks started off at
relatively low speeds. The fastest hard disks were
SCSI disks at 7200 rpm
spindle speeds but these were used only in server environments. However,
7200 rpm reached the desktop PC a few years ago and newer desktop hard
disks even run at 10,000 rpm. That’s a lot of revolutions per minute.
Fortunately, these advances in hard disk speeds have been accompanied by
new technologies to limit the noise the disk generates. Most hard disk
manufacturers now either offer a range of quiet disks or use special quietening techniques on all their disks. If you’ve got an existing
older hard disk that you need to control the sound on - or even a newer
disk that’s just too noisy for you - here are some products that may
Hard disk mounts:
These are L shaped metal blocks with rubber in between. Hard disks
typically have four contact points with the case i.e. at the four holding
screws. If you
have a spare 5.25” bay however you can use these mounts
and move the hard disk to the larger bay. At each corner of the disk
you’ll have one L shaped mount screwed on to the hard disk and one on to
the bay ensuring that the metal from the hard disk doesn’t touch the
metal on the bay and therefore reduces vibrations transferred to the case.
Hard disk heat sinks,
like in the picture here, serve two
purposes. They have four rubber rings
that act like the mounts above which prevent the hard disk coming into
direct contact with the case. They do also have a heat sink consisting of
a collection of copper pipes that dissipates heat from the higher spindle
manufacturers sell complete enclosures for your hard disk. An enclosure
will typically fit in a 5.25” bay and completely contain your hard disk
i.e. a little box into which your hard disk vibration and noise disappears
... theoretically. Please do be very, very careful with these enclosures though.
Check that they are rated to handle the spin speed of your hard disk and
are capable of getting rid of the heat the hard disk generates. Some
enclosures dissipate the heat via one or two little fans. And, as with any
fans, these will generate some noise themselves so you’ll have to balance
that against the saving of hard disk sounds.
Recently there have been major advantages in storage
technologies. Flash memory cards have been getting bigger and bigger. Soon
there will be storage devices like flash memory cards that will hold an
entire operating system and your other files thus dispensing with the
moving hard disk altogether. In fact such devices do exist right now but
they are so horrendously expensive that they are used only in very select
situations like space exploration and military applications. (At the last
check a half decent size “disk” was $40,000).
Power Supplies: In many PCs this is the
component that generates the most noise. When choosing a PSU for your PC
shopping around can save you a lot of sound. Manufacturers of quality PSUs
normally have a noise rating listed along with the technical specs.
Further, using the right wattage of PSU for your PC does help, if you
don’t need a 550 watt power supply, why buy one. It will probably make
the same amount of noise even if you are only demanding 200 watts of power
out of it. If the budget stretches to it there are some PSUs now available
that are completely fan-less. These tend to come as standard on very
expensive cases that are marketed as quiet cases, but some of them are
also available for purchase to fit in any standard PC. They dissipate heat
via a large radiator type heat sink that sits outside the PSU and outside
the PC. Some of the heat sinks stick out a few inches behind the computer.
Graphics card “VGA heat pipes”:
Performance graphics/video cards do of course generate a lot of
heat. In fact the processors on today’s high end graphics cards have
more power than the main CPU in any PC you’ve had for a few years.
Because of the international standardisation on size and location of PCI
and AGP cards the graphics card fan has to be fairly small. This of course
means that it needs to spin faster to keep the card cool. Some cards have
high performance RAM on their flip side and sometimes these need active
cooling too. The best route to take with graphics cards is - as with the
PSUs described above – if you don’t need the power then settle for a
lower tech option. But if you’d still like to lower/remove the sound
from the graphics card’s fan you’ll have to shop around for a VGA heat
pipe like the one in the picture below. To fit it you’ll have to remove
the heat sink and fan your graphics card came with (and lose the
manufacturer’s warranty on the card for “tampering” with it) and fit
a VGA heat sink instead. This spreads the heat over a much wider surface
area and provided you have sufficient airflow over the VGA heat sink/heat
pipe you may get away with not having a fan to cool your graphics card
Thermal paste: This is a vital product in any
PC builders' kit. It’s normally applied between a processor and the heat
sink and helps conduct the heat away from the processor. Too much of the
paste is counter productive, you need only a thin film.
Chassis Fans: The most popular size of chassis
fan is the 80 mm. However, 120 mm fans are now becoming quite popular –
and therefore available - because they do tend to generate less noise. Not
all 120 fans may fit on your case as the case may have screw holes for
only the 80 mm size. There may be adaptors available that will allow you
to use a 120 mm fan in a location normally reserved for an 80 mm. Some of
these chassis fans are quite clever; they come with ducting that leads to
the CPU to provide a more direct route for CPU heat to leave the case.
In quality cases you will normally have at least one
or two chassis fans at the front of the case drawing cool air in. Often
this air is dragged in over a dust filter or a grill. This air movement through the filter/grill can cause a small bit of noise.
In our opinion it’s not worth removing an intake filter to reduce
sound. The filter does serve an important purpose. Removing a filter may
well save you a fraction of sound but the extra dust going into your PC
and settling on fan bearings will more than negate that benefit.
Chassis fans range from about 15 dba to about 30
Quality case manufacturers who provide chassis fans tend to provide fans
that generate less than 20 dba.
Regulators: Most electronic shops will stock a
variety of devices that can control fan speeds via resistances. It is
possible to have all the fans in your PC, from your PSU to the CPU to the
chassis fan running only at the lowest rpm they need to run to keep the
relevant parts within your pre-defined operating temperature range.
Automatic adjustments of power to a fan can make it spin faster or slower
and these automatic adjustments could be based on the output readings from
temperature sensors. These are all products for the professional or the
very keen enthusiasts. Attempting to fit them yourself may result in some
burnt out components before you get fully familiar with them and fully
competent at setting them up.
quiet PC specialists, more info and prices on quiet PCs