SilverStone Decathlon DA700 power supply

MP3 SOUND RECORDINGS

These recordings were made as 24-bit / 88 kHz WAV files with a high resolution, lab quality, digital recording system inside SPCR's own anechoic chamber (11 dBA ambient), then converted to LAME 128kbps encoded MP3s. We've listened long and hard to ensure there is no audible degradation from the original WAV files to these MP3s. They represent a quick snapshot of what we heard during the review.

These recordings are intended to give you an idea of how the product sounds in actual use — one meter is a reasonable typical distance between a computer or computer component and your ear. The recording contains stretches of ambient noise that you can use to judge the relative loudness of the subject. Be aware that very quiet subjects may not be audible — if we couldn't hear it from one meter, chances are we couldn't record it either!

Each recording starts with 6~10 seconds of room ambient, followed by 10 seconds of the product's noise. For the most realistic results, set the volume so that the starting ambient level is just barely audible, then don't change the volume setting again while comparing all the sound files.

Sound Recordings of PSU Comparatives

Caution! It's important to understand that these recordings cannot be compared directly to the recordings made in the anechoic chamber. The live room in which they were made echoes and has a noise floor 4~8 dBA higher, the microphone has a much brighter sound quality and a different output level, and even the dBA measurements are wrong below ~25 dBA — they are higher by 2~8 dBA than they would be in the chamber with the new test gear. These recordings are here mostly for the record.

Please note that other than the Enermax Modu82+ 425W, PC Power & Cooling Silencer 610 and the NesteQ 700W, all other PSU recordings were made in the live test room, whose acoustic are considerably noisier and reverberant than the hemi-anechoic chamber. The comparative database will get better as we update some previous tests and recordings, and as more reviews are added to the mix.

Ambient acoustics of the anechoic chamber vs the live room - Some of you will be interested to hear this difference. The recording begins with 8 seconds in the anechoic chamber, then 8 seconds in the live room, followed by a few seconds in the anechoic chamber. The SPL levels, as mentioned before, were 11 dBA and 18 dBA respectively. It's interesting to note that the hiss many SPCR forum members attributed to electronic noise is, in fact, not so; it's part of the live ambient, due at least partly, to reflections at higher frequencies in the room. This is obviously absent in the chamber. (However, we did make a change to a new microphone which also has considerably less noise than what we were using before the anechoic chamber, so some of the hiss in past recordings was caused by microphone noise.)

CONCLUSIONS

The Silverstone delivers very clean power with tight voltage regulation to its full rated output. AC ripple is exceptionally good as well, among the best we've seen. Its efficiency is a touch lower than many competitors, although this models is admittedly not certified 80 Plus. Cooling is excellent, as the temperature rise through the unit remained in single digits to past 500W in our test rig. The modular cable system is very nice. That every cable can be removed may seem a bit odd because some of them always have to be used, but in some instances, this can ease the installation process.

Acoustic performance is fairly good, staying quiet in our test setup till around 300W. The noise jumped above 30 dBA@1m at 400W, a little lower than expected, considering Silverstone's confidence that it would best the Enermax Modu82+ 625W. The sound signature at idle is not particularly smooth, there being a kind of tonal, buzzy quality. The quality may get better as the fan speeds up, with the buzzy quality become less audible over the turbulence noise.

Is it possible that the fan in this DA700 sample is subtly damaged? Nothing is impossible, and damage to fan bearings is quite common, in my opinion. It's hard for shipping handlers to break a fan and make it inoperative inside a PSU. It seems much easier to slightly damage a PSU fan in transit, enough to make it sound noisier without causing any other significant deteriorations. Over the years, I've come to appreciate how often this happens. If SilverStone feels this is the case, we'd accept a couple of replacement fans to try.

In any case, even if the growly quality of the sound could be subdued, the DA700 is not likely to match the Enermax Modu82+ 625W sample which Silverstone pitted it against. The gap is too big. It's not that far off; for many users, the Silverstone is close enough to their home or office ambient noise level that the difference might be moot. For an aurally sensitive listener in a quieter space, however, the Enermax sounds a lot better. (So do the 850W and 1000W Zalman models, if my acoustic memory can be trusted.) One of the newer, higher efficiency, lower SPL models offered by SilverStone (such as the 80 Plus Silver rated ST70EF) would probably be a more appropriate model to challenge's SPCR's short list of top-rated PSUs.

In summary, the DA700 provides excellent electrical performance, keeps itself safely cooled, and doesn't kick up a noisy fuss. It is not the quietest or most efficient PSU we've reviewed... but it could be suffering from a slightly "off" fan. Keep the overall power demand to under 400W, or use it in a case that keeps the PSU intake separate from the rest of the system's heat, and the DA700 would be a prime candidate for a diehard PC gamer.

Much thanks to SilverStone Technology for this review sample.

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SPCR Articles of Related Interest:
Power Supply Fundamentals
Recommended Power Supplies
SPCR PSU Test Rig V.4
Enermax Modu82+ 625W
Seasonic S12 Energy Plus 550 and 650
NesteQ ECS7001 700W PSU: A Modular Twist
Corsair HX520 & HX620
Zalman ZM1000-HP: Quiet KiloWatt PSU

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