Introduction

With the increasing speed of processors, heat has become a big issue with computers. The primary ways to solve this are to add more fans or increase the speed of the fans. Both of these methods add to the ambient noise generated by the computer. Computer noise is one of the fastest growing concerns among consumers when it comes to the physical attributes to a computer system and manufacturers are starting to listen.

Many people may not have heard of StarTech.com. Their business focuses on replacement and hard to find parts. But if you are in need of a particular type of screw, a power supply, specialized cables or other unusual parts, they likely have it in stock. They have recently begun expanding their line of silent power supplies to include higher wattages that many enthusiasts require. With the help of the people from StarTech.com, I'm able to take a closer look at their ATXPOW480HS Silent 480W ATX power supply.

The Power Supply

StarTech.com ATXPOW480HS

To try and reduce the amount of noise generated by the power supply, the Silent 480W ATX has a larger 120mm fan that runs at reduced speeds over smaller 92 or 80mm high-speed fans. The fan has three distinct speed levels that range from 750rpm to 1000rpm based on the temperature inside the power supply. In addition to this, the external fan of the power supply was removed to include a large number of holes for increased airflow. While all of this will not totally eliminate the noise from the power supply, is does significantly reduce it. In fact, it is likely that the noise generated by the CPU heatsink or case fans will overshadow the noise generated by the power supply even when it is running at the fastest speed.

Back panel of the StarTech ATXPOW480HS

The unit features a large number of connectors. One of the nice additions is the inclusion of two Serial ATA power connectors. As the serial ATA standard becomes more commonplace, hopefully additional connectors will be added to future models. Other connectors include the standard ATX power connector, ATX12V connector, seven 4-pin molex connectors, two 4-pin floppy connectors and a 6-pin Auxiliary power connector. The ATX power connector is bundled inside of a plastic mesh sheath. All of the cords are long enough to support the power supply being in a full sized tower case. This could make the 480W version a bit difficult to fit in a small size case although it was able to fit into the Antec Sonata case without much difficulty.

Connector cords running from the StarTech ATXPOW480HS

Power Specifications

Below is the power specification table listed on the power supply.

The first thing to notice on the label is that the +3.3v and +5v lines share the same rail inside of the power supply. The other way to tell this is that the combined wattage on the label for these lines is 275W but if calculated for each of the lines individually, the combined output would be 324W. This shouldn't cause a problem as most power supplies tend to be designed this way, but it can lead to power fluctuations along these voltage lines. The +12v line has a very ample 312W output which should supply all of today's modern desktop computers with sufficient power for a large number of internal drives and fans. The combined total wattage of the unit is 473W which is very close to the advertised 480W for the unit.

Testing

Since the focus on the StarTech.com Silent 480W power supply is on low noise operation, the components selected for the testing platform are designed to try and generate as little noise as possible. In addition, the voltage is being compared to the readings from the default Antec TruePower 380W power supply that comes standard with the Sonata case used in the test platform. With this is mind, here is the hardware used in the testing:

All of these testing components will not draw too heavy of a load from the power supply. As a result, I'm not able to verify the unit's actual wattage output. Instead the testing looks at the voltages supplied across the various lines to the motherboard during low and high computing usage. This lets us see how close the power supply is to the specifications and how much fluctuation there is in the lines.

Readings of the voltages were taken via the Motherboard Monitor 5 utility. Usage was tracked over a several hour period of both idle usage and heavy computing usage simulated through a series of benchmarks using SiSoft Sandra's burn-in wizard. Voltages were recorded every 30 seconds and the highest and lowest readings for each unit were taken. This was done both for the default Antec TruePower 380W and the StarTech.com Silent 480W power supplies.

Overall, the StarTech Silent 480W did a very good job. It was much closer to the reference voltage levels than the Antec TruePower 380W. In particulate, its greatest variance was with the 3.3v rail under heavy load, and even then it was only off by 7%, below the industry 10% margin. By comparison, the Antec TruePower 380W was reading the limits with a 10% variance on the 5v rail. The only drawback in the voltage ratings seems to be the wide difference in the 3.3v rail between an idle load and a heavy processor load. These numbers are still within industry standards though. It was interesting to note that the fan speeds were a higher than the specifications.

Conclusions

Overall, the StarTech.com ATXPOW480HS Silent 480W ATX power supply tested very well. Its voltages were well within reason and tighter than that of the Antec unit supplied with the Sonata. A bit more of a disappointment is the noise. While the unit is named silent, it definitely is not. The noise generated by the unit will typically be less than the other components of a PC that make it appear silent, but as long as there are moving parts such as a fan, there will always be noise. The price is also fairly high for the 480W unit. If your system doesn't have a large number of fans or drives, a lower wattage unit such as the 380W will provide enough power for today's AMD and Intel processors but at a significantly lower price.

In the end, if you are looking to build a low noise computer or to reduce the noise generated by an existing power supply within a current computer, the StarTech.com ATXPOW480HS Silent 480W ATX power supply should be one to consider.

Manufacturer's Site