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High Performance Quiet PSUs

It is highly recommended for a modern PC system to incorporate a high-quality PSU capable of coping with the power demands of the most up to date components. However, a powerful PSU does not necessarily need to be noisy! Quiet PC's range of near-silent power supply units range from 300W to 503W and all have quiet features to ensure a virtually silent PSU. These tried and tested PC power supplies come from QTechnology and Zalman.

QTechnology Gold Series PSUs Ultra-quiet 120mm fan PCI-E, 20/24-pin connecters From 17 dB(A) 350W, 400W

Zalman Noiseless Switching PSU Very quiet 80mm or 120mm fan Active PFC From 18 dB(A) 300W, 400W, 460W

Upgrading a noisy PC power supply

With any significant upgrade of your PC you should consider whether your new components need a more powerful and quiet PSU. Our range of virtually silent PSUs are able to handle the most demanding power requirements. Smooth, clean outputs, excellent regulation, effortless power delivery, rock-solid reliability day in, these are all features which make these quiet PC power supplies the number one choice for the discerning customer.

Why do you need a high quality PSU?

Compromising on your PSU can mean compromising on system stability. Poor voltage regulation and filtering from your PC power supply can cause component stress and cause your system to crash randomly. This can cause the loss of important data and ultimately decrease the lifespan and reliability of your PC. All of our quiet PSUs are standard 100% ATX compatible units. They are AMD approved and conform fully to Intel's ATX specification. If you are looking for a non-standard ATX, miro-ATX or a replacement power supply for a Dell PC click here.

How can PSUs contribute to PC noise?

As the PC Power Supply Unit converts power from AC to low-voltage DC, some electricity is unavoidably converted to heat. To prevent the PSU getting too hot this heat is removed by a built in fan (or two). Fans can be a major cause of PC noise due to airflow and fan bearings. The virtually silent PSUs we have selected all address this by using innovative technology to optimise efficiency and reduce fan noise. For example our power supplies have a built-in temperature controlled fan. The fan's RPM will increase depending on the internal temperature of the PSU. Other power supplies go one step further and turn the fan off completely. It only rotates when the internal temperature of the PSU reaches a certain point. From a noise point of view this gives you quietness you would expect but also the peace of mind that the fan will start if things get a little hot.

Recommendations for choosing a quiet PSU

If you are unsure which wattage power supply to purchase, take a look here. This page provides information regarding what wattage each component uses inside your PC.

Below 400W
If you require a PSU below 400W and your budget is the ruling factor, then the Zalman 300W power supply is the best solution, it is extremely good value for money. But if you like a more powerful and even quieter power supply the QTechnology 350W PSU is ideal!

400W to 500W
For those customers who need 400W of power then we recommend the QTechnology 400W PSU. The Zalman 400W has one 80mm fan so it is marginally louder than the QTechnology 400W PSU which has a 120mm fan. 

QTechnology Gold Series PSUs

For pricing and availability, please click here or order at the top of the page

Our best-selling QTechnology Ultra-Quiet PSUs are the perfect choice for the vast majority of PCs and will give astounding results at a great price! Many British professional audio workstation manufacturers are now using these units in their systems. Whether you are building your own studio PC, or you simply want to maintain a quiet home environment, the QTechnology virtually silent PSUs really do deliver.

Building on the success of their earlier PC power supplies, QTechnology have made available three new ultra quiet large-fan quiet PSUs, rated at 350 watts, 400 watts and now 460 watts. They have an integrated 120 mm fan which provides a similar air flow to conventionally designed PSUs, but because the fan is larger in diameter it spins much more slowly. Therefore it is even quieter!

Instead of the fan being located at the back of the PSU, the 120 mm fan is on the underside (assuming you have a tower system), such that it sits right next to the CPU cooler. Because of this, the power supply not only runs quietly, but also greatly assists in reducing the temperature of the processor and the ambient case temperature. Warm air is expelled through the large grille area on the rear of the power supply. These power supplies are exceptionally quiet, even when the loading and temperature of the unit increases.

It is now even possible to monitor the speed of the power supply fan. This option is available with the 460 watt version only, and requires a spare 3-pin fan header on the motherboard.

PLEASE NOTE - It has come to our attention that another company called "Q-Tec" has recently entered the market and is causing confusion by offering low cost PSUs in competition with QTechnology. Please be certain that neither QTechnology nor Quiet PC have any connection whatsoever with Q-Tec. We know several instances of customer being disappointed with the quality and noise level of Q-Tec PSUs only to find out later that the product they had bought was not made by QTechnology. If you are not buying directly from Quiet PC, please make sure you know what you are buying, and if the price seems too good to be true, it probably is! To add further to the confusion, we now find that there is a third company calling themselves Qtech who have started offering pre-built PCs. Again, our position is that we have no association with them.

QTechnology Specifications

All QTechnology power supplies come with a full 24 months manufacture's warranty

Product Reviews

"Listen to the KUAC on-air radio review here" (requires RealPlayer)

" The box has the quote, "The ultra quiet power supply", written on it. Unlike many others, it lives up to it's claim." - PimpRig (400W, 120mm fan)

" I was impressed with how quiet it was and how nice it looked" - Creative Mods (350W, 120mm fan)

" For those who are looking to build a quiet system or to replace a noisy power supply, definitely check out the Q Technology Gold Series 350W Power Supply." - PC Synapse (350W, 120mm fan)

" The overall build quality on this product is excellent both on the outside and inside." - 3D Gameman, Video Review (400W, 120mm fan)

Zalman Noiseless Switching PSU

For pricing and availability, please click here or order at the top of the page

Zalman are famous for their Computer Noise Prevention System (CNPS) components. They have now taken this to the next step by producing two exceptional near-silent PSUs. Take a closer look at the ZM300B-APS and ZM400B-APS. These new quiet PSUs offer the advantage of SATA hard drive connectors over the old "A" product versions. By implementing heat-sensor circuitry that controls the cooling fan's speed (rpm) in relation to the temperature within the PC power supply, emanating noise has been greatly reduced. The graph below shows the CNPS characteristics of the product. When the temperature inside the PC power supply is 55° C or less, the cooling fan will operate in 'Quiet' or 'Silent' mode, i.e. below 25 db(A).

Complies with Intel ATX12V ver 1.3
The ZM300B-APS and the ZM400B-APS comply with Intel ATX12V Ver. 1.3 S-ATA power connectors supporting S-ATA Ver. 1.0 compliant hard disk drives.

Simplifying Source Input - Free Voltage
Unlike products with passive PFC where the customer must set the operating voltage with a manual switch (115 VAC / 230 VAC), these products can be used with any normal AC input source ranging from 100 VAC to 240 VAC.

Improving Power Factor & Eliminating Harmonics through Active PFC
By implementing Active PFC, the power factor (PF) is improved from 75% (Passive PFC) to 94% (at full load), while harmful harmonic frequencies are reduced well below regulatory requirements.

Supplies Stable Power to Intel Pentium 4
By including an ATX12V 2x2 (4-pin) 12V power connector and an auxiliary 5-pin power connector, these quiet PSUs can provide stable power to Intel Pentium 4 CPUs, which need 6A of current from each power rail.

High Efficiency Power Supply
Designed with a high switching frequency and low power-loss circuitry, the efficiency of these products exceeds 75% (at full load).

Zalman's newest power supply is slightly different to the PSUs mentioned above. The most obvious difference is that the new 460W PSU is supplied with a 120mm fan compared the to 80mm fan supplied with the 300 and 400W power supplies, making the ZM460-APS power supply run even quieter than the other models.

This power supply is also ATX Ver. 2.03 / ATX12V Ver. 2.01 compatible and therefore is supplied with all newest types of connectors, including two PCI-Express, 20 and 24-pin ATX connectors and 8-pin EPS12V which splits into two 4-pin ATX 12V connectors. There are also two 12V rails with a combined output of 30A, which is ample power for high end systems. All cables are braided and the 4-pin Molex connectors come with "EZ Grip" connectors. This allows you to connect and disconnect the plugs with minimum fuss.

Parts list One Power Supply Unit One FAN Multi-connector (ZM-MC1) One S-ATA power convert cable One PCI Express VGA SLI sub-Cable for power conversion One User’s Manual Zalman Velcro Cable Ties

Zalman Specifications

All Zalman power supplies come with a full 12 months manufacture's warranty

The ZM-MC1 is included free with every Zalman power supply and is used to supply +5V or +12V power to any additional fans that you may wish to install. Connect it to a power supply hard drive connector and simply attach the fan(s) to the 3-pin connectors at the other end. All Zalman's power supplies come with very handy velcro cable ties, to encourage you to tidy up those cables!

Product Reviews

"It is dead quiet, I have to turn every fan off to even hear a whisper coming off of it. It simply does its job and does it very well." - HTPC News (ZM300B-APS)

"Impressively constructed and designed for excellent cooling while maintaining low noise for a wide range system loads..." - Silent PC Review (ZM300A-APF)

"The ZM400A was completely silent..." - Hardware Review (ZM400A-APF)

"Zalman's ZM400A-APF is a solid power supply that really performs well. A definite plus is its low noise levels." - Tom's Hardware (ZM400A-APF)

Non-standard / Micro-ATX PSUs

Our current stock of ATX power supplies are all standard, measuring 86 x 150 x 140mm. If you are looking for a replacement micro-ATX or a non-standard PSU then unfortunately we do not have any thing available.

Dell owners

Our quiet power supply units are fully ATX compliant, which means that they will work in any standard ATX PC. You may or may not realise that PCs manufactured by Dell may use a power supply which often looks to be industry-standard, but in fact employs different wiring which makes replacement of the power supply with an ATX model impossible. This approach ensures that when you need to replace or upgrade Dell components, the only place you can buy them from is Dell! With this in mind, Dell owners please check that our PSUs are compatible with your system before you buy. However, as we know Dell 8300 and 4600 models use standard ATX power supplies you can use any of our power supplies in these machines.