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Desktops

Build the ultimate quiet PC

Having a high-speed PC is every techie's dream. Unfortunately, fast PCs generate significant heat and require ventilation by noisy cooling fans. This can turn your PC pride and joy into a whirring annoyance -- particularly when it's being used during quiet periods or at night.

Some PCs run as noisily as 50db -- that's nearly as loud as an electric toothbrush or a washing machine. As you can imagine, the whine of a dozen cooling fans can distract you during work and diminish your enjoyment when playing music or video on your PC. The last thing you want during a tear-jerking love scene is the click of a hard drive or the whir of a DVD drive.

In this feature we'll take you through the necessary steps required to turn your noisy computer into the ultimate quiet PC. It'll be so quiet, in fact, you'll wonder whether it's even switched on. Some steps are as easy as pie, others require a modicum of technical knowledge, but all of them will help eliminate unwanted noise forever.

If you're serious about making your PC quieter you should first ensure the case absorbs as much internal noise as possible. Many manufacturers sell cases with pre-installed sound-deadening materials, one of the best examples of which is the Silentmaxx ST11-PRO acoustically lined case (£100 from Quiet PC). As you can see in picture 1, there's sound-deadening foam already installed in the side panels, helping to hush any noise the PC might produce. The case also has ample ventilation, so you can more easily add fanless components without risk of overheating.

Not got enough cash for a new case? Then you can modify your existing chassis. Among the best sound-deadening materials is the Acousti AcoustiPack Deluxe (v2) SE acoustic material kit (£34 from Quiet PC). It's essentially a pack of sticky-back foam used to line the panels of your case. It comes in pre-cut packs for a small number of cases, but you can easily cut custom shapes with a pair of scissors, as you can see in picture 5. The deluxe pack comes with two foam blocks that you can shove into your 5.25-inch optical drive bays to reduce noise further.

While you're tinkering with your case, you may also consider attaching some anti-vibration feet. Vibration from inside the computer can be transmitted through the base of the chassis, causing unwanted noise -- particularly if your PC sits on a hard surface. If the feet of your case are firmer than the texture of a well-done steak, simply detach them and attach some vibration-absorbing feet such as the Nexus Anti-Vibration Mounting Kit (£12 from Kustom PCs).

The oft-forgotten power supply unit (PSU; see picture 1) is a major contributor to PC noise. Most have one or even two fans whirring constantly inside them. The more powerful the PSU, the more cooling it requires, and the more noise it generates. Applying sound-deadening material or removing the fans is a potential fire hazard, but you can buy PSUs that are specially designed to run quietly.

In pictures 2 and 3 we show how we swapped the ageing PSU from our PC with a Nesteq Semi-Fanless ASM PSU (£139 from Quiet PC). The words 'semi' and 'fanless' seem incompatible, but it provides a whopping 620W of power, and its cooling fan only spins very occasionally -- once every minute or so for about ten seconds. This makes it quieter than a Carmelite monastery. You can adjust the fan's spin speed (via the knob on the rear) for even more tranquility.

Finally, you should replace the exhaust fan from your case with quieter alternatives. In pictures 4 and 5 we show how we replaced a standard 120mm fan from our existing Antec P150B case with an Acousti AcoustiFan: DustPROOF 120mm fan (£19 from Quiet PC), which runs more quietly and provides the same level of ventilation.

Now you've sorted the case and the ventilation, it's time to focus on the components. The biggest culprits of noise pollution are the heatsink and fan that cool a PC's central processing unit (CPU). Most computers ship with the standard heatsink designed by either Intel or AMD. These are designed to provide optimum cooling, but noise reduction isn't their forte.

For the ultimate quiet CPU, swap your desktop processing unit for a laptop model, as the latter have lower power demands and require less cooling. We've chosen an Asus N4L-VM DH motherboard (£98 from Dabs.com -- picture 1) as it's designed for desktop use, but accepts Socket 479-type laptop CPUs, including the Intel Core Duo and Core Solo chips found in modern laptops.

We've paired this with a Pentium M 750 CPU (£183 from Amazon UK) running at 1.86GHz (picture 2). This isn't the fastest chip in the world, but it stays cool during use and doesn't require a massive fan. The heatsink and fan included in the Asus N4L VM DH motherboard package (picture 3) is perfectly adequate as it only spins occasionally. We'll control just how much it spins in step 8.

If your budget doesn't stretch to a whole new CPU and motherboard, we recommend replacing your current heatsink with a noise-reducing alternative. First identify your motherboard's CPU socket type then choose a quiet heatsink and fan that's compatible. We've chosen the CNPS9500-AM2 AMD Aero Flower Cooler (£33 from Quiet PC) to go with our existing Socket 939 AMD Athlon 64 FX60 CPU (picture 4).

We like the Aero Flower Cooler's striking design (it glows green in the dark) and it has a manually adjustable fan-rotation speed of between 1,350 and 2,650rpm. This means you can control exactly how much noise it makes. You'll need to crank it up to its full velocity when running demanding applications, but you can run it at the lowest setting for everyday tasks like Web browsing or watching a DVD.

The graphics card is a major contributor of PC noise -- arguably more so than the CPU. This is because they usually ship with tiny fans that whir incessantly. We've swapped our standard ATI Radeon X1800 XL card for a completely fanless MSI ATI Fanless X1600XT 256MB DDR3 card (on its own in picture 1, and installed in the motherboard in picture 2). The standard ATI cooling fan has been replaced with a fanless heatsink, so it's completely silent. Heat is dissipated over a set of heatpipes instead of by a fan. Despite it being fanless, this card is a solid mid-range component that can cope with most of today's modern 3D games, such as Half-Life 2 and Doom 3.

If you don't have the funds to splash out on a new fanless card, you can modify your existing card with a quieter cooler. As you can see from picture 3 onwards, we've removed the standard ATI cooling fan with a Zalman VF900-Cu dual-heatpipe VGA cooler (£28 from Quiet PC). The process can be quite tricky, but if you've got a tiny screwdriver and a modicum of courage it'll be well worth it.

In picture 3, we've unscrewed the rear bracket of the standard cooler, then removed the combined cooler and heatsink from the front of the card in pictures 4 and 5. In picture 6 we've attached tiny heatsinks (included in the Zalman package) to the card's memory chips. The final step simply involves re-attaching the quieter, larger Zalman CF900 fan, as can be seen in picture 7.

Another component that potentially deserves an anti-social behaviour order is the motherboard chipset. These chips contain functions that support the CPU, and one in particular -- the northbridge -- can become quite hot. Some motherboards have fan-cooled northbridge chips that contribute a great deal to the overall symphony of noise. Northbridge fans are prone to malfunction, so if your PC is making a bizarre squeaking noise, chances are it's the culprit.

We've opted for motherboards with passive (fanless) chipset coolers (highlighted in picture) so there's no chance of noise or a fan malfunction. However, if your motherboard has an active chipset cooler you can swap it for a passive third-party model such as the Zalman ZM-NBF47 Northbridge Flower Heatsink (£10 from Quiet PC). Simply uninstall your existing heatsink by unscrewing the tiny screws beneath the motherboard and attach the replacement model in exactly the same manner. See your own motherboard manual for exact instructions.

If you're shopping for a new motherboard, try to avoid those that come with fans that cool the electrical capacitors. These are quite rare, but if you do end up with one you'll be stuck in a world of unnecessary noise.

There are no fans in hard drives or optical drives, but they do contain a load of moving parts that can make a racket. Whereas some drives are designed for high capacity, others, such as the Samsung HD300LJ hard drive (£90 from Quiet PC) are designed for quietness. The HD300LJ (shown on the right of picture 1) uses fluid dynamic bearings, which have a thin layer of lubricant between the shaft and the sleeve of the bearing, making it more quiet and robust.

We've gone a step further by enclosing the quiet hard drive in a sound-deadening Silentmaxx Aluminium HD silencer (shown on the left of picture 1; £37 from Quiet PC). Pictures 2 and 3 show how to insert and fix the hard drive into the silencer, while picture 6 shows us installing them into the 5.25-inch drive bay of the Silentmaxx ST11-PRO chassis.

The silencer shrouds the disk (see picture 4), except the rear ports, which are still accessible, as you can see in picture 5. Don't worry about the drive overheating -- the enclosure acts as an enormous heatsink that channels heat away from the disk. It also comes with a set of rubber mountings on either side, which absorb the vibrations of the disk drive.

High speed optical (CD or DVD) drives can be one of the biggest contributors of PC noise. Even 24x models can have a whopping spindle speed of 12,000rpm, and if you're using a disc that's slightly warped, the resulting noise and vibration can be infuriating.

Typical drive speeds can reach in excess of 48x, which gives a transfer rate of 7,200KBps, but the data rate of an MP3 file is only 16KBps (128kbps), so you'd only need a speed of around 0.1x. As a result you may want to set the speed of your drive to a much lower level. CD Speed 3.1 (picture 7) is an application that can be used to set the read speed of a drive, reducing its spin speed and any subsequent vibration. Remember to crank the drive speed back up to its maximum when installing large software applications from a CD or DVD.

Now you've got your fancy new fans running quietly inside your PC, you'll want to tweak them so they're running at peak efficiency and quietness levels. For this we recommend a Zalman ZM-MFC1 Multi-fan Speed Controller (picture 1 -- £26 from Quiet PC) as this lets you independently control the speed of each fan in the PC.

This device can control up to six fans: four via control knobs similar to those on dimmer switches, and two by switching the electrical voltage from 12V to 5V -- which causes them to run slower.

We've attached the fan-speed controller to the CPU cooler on our Asus motherboard (picture 2) for extra flexibility. The process for doing so is quite simple: one cable is attached to the fan controller port on the motherboard, while the power lead for the fan itself attaches to a bypass connector on the fan controller. The controller then sits neatly in a 5.25-inch drive bay at the front of your case, where you can tweak settings on a whim (picture 3).

Okay, we're almost finished. Now you've got all the components in place, you probably have a PC that runs quietly but has wires that make it look like Spaghetti Junction (picture 1). You may think this is harmless, but a mass of cables reduces the efficiency of the airflow inside your PC, which can cause it to get hotter than normal.

In a standard PC, the internal cooling fans will be able to cope with the increased heat -- they'll simply work harder, and will therefore produce more noise. But in the PC we've built, we're using so many fanless components that there are no fans to fall back on. This means your components could overheat, or your PC could become unstable and shut down to save itself from frying!

We recommend using cable ties to secure cables. A 150-piece set of colour-coded cable ties costs just £2.99 from Maplin. Make use of them (as we've done in picture 2) -- they'll make your PC much happier in the long run.

Our final piece of advice is maintenance. Like most household items, PCs gather lots of dust, which can also cause the computer to overheat -- dust build-up insulates components, impacting on their ability to stay cool.

PC fans also suck in a good deal of dust. This dust can attract moisture, forming a grimy cocktail that can corrode components, including cooling fans. Damaged fans can easily be spotted as they tend to make lots of noise -- replace these as soon as possible to avoid trouble in the long run.

We also recommend removing dust from your PC by using an ordinary vacuum cleaner (as demonstrated in pictures 3 and 4). Make sure you switch the PC off first then go around the entire case, paying particular attention to the fans and the power supply. Do this on an annual basis at the very least -- not only will your PC stay running quietly, but it'll also perform more reliably.

Congratulations! If you've gone the whole hog and followed all our steps, your PC should now run more quietly than 99 per cent of those on the market. Even if you've only used a few of our tips, you should still have eliminated a significant amount of unwanted racket. Sit back, put your feet up and revel in your newfound peace and quiet.