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Review of Silent 400w Power Supply
SnowPunk98 writes "OCModShop has done a review on a SilenX 400w 14 dBA PSU "The power supply doesn't boast any flashy designs or cool colors however that is not the purpose of this power supply. Silence is what the main goal of the unit is and there are tons of features to help achieve that.""
so here's another review of it, on a different site...
I have recently become totally fed up with the high pitched whine my main work machine made, so I decided it was about time to do something about it. I bought a Zalman silent PSU, a Zalman flower CPU cooler, two Zalman silent case fans and a Zalman heatpipe graphics card cooler. When they say silent, they aren't totally silent (except for the heatpipe graphics card cooler which has no fan), but they're pretty damned quiet.
My PC is transformed, the loud, obtrusive, high pitched whine has now been reduced to a quiet, low pitched rumbling. I struggle to hear it when I'm 10 feet away, and even when sitting by it and working it's so much quieter it's much more enjoyable to use. Music is also a much nicer experience without the fan noise. I've even found that my CPU runs cooler with the Zalman heatsink than it did with the medium priced heatsink I had in there before.
This could give you a clue. ...
14dBA is way below whisper
Well.. 0dB would be ideal, but most people cannot hear sounds that low... especially geeks with big stereo systems.
This page has an excellent table of information on various dB listings.
According to it, human breathing at 3 feet is 10dB... can you hear people breating from 3 feet away? (I can't.)
SilenX 400w 14 dBA PSU
Date : Sunday, January 25, 2004
Author : SnowPunk98
Vendor : SilenX
Introduction
I have reviewed a lot of power supplies over the years here at OCModShop and now I look at the SilenX 400w. This power supply claims to be the quietest active cooled power supplies on the market. I have done reviews on many other silent power supplies from many other companies. Some have been as quiet and they boasted to be and others were much louder than they should have been. This power supply features Over Voltage Protection, Over Power Protection, and Short Circuit Protection. All of these features will ensure that the power to your system is stable and fixed. I don't like loud systems at all, before I got this power supply I was using the True Silent 450w PSU I previously reviewed because it was the quietest I have encountered so far. I will be using the True Silent power supply to compare this SilenX one to see which is quieter.
The power supply does not come boxed, rather it comes in a plastic bag with the power cord supplied. The power supply was shipped via USPS Priority Mail and was in one of their boxes. The power supply was protected well during shipping with packing material and came undamaged. I think that SilenX should really look into getting a box for their power supply, for many different reasons.
The power supply doesn't boast any flashy designs or cool colors however that is not the purpose of this power supply. Silence is what the main goal of the unit is and there are tons of features to help achieve that. It would be nice if there was something extra as far as looks is concerned with this power supply if it did not raise the price.
The back of the power supply has an on/off switch, 110/220v toggle, and power connector. The 80mm fan that is used as an exhaust has a unique blade design and hybrid immersion bearings to lower the noise level. Instead of the traditional metal screws the fan is held in place by a silicone composite fan vibration dampening system. The fan on a power supply is what makes the noise so the quieter the fan the quieter the it will be.
Because this power supply is designed to be silent there is only one fan so there needs to be some decent heatsinking inside of the unit to keep it cool. One thing I noticed is that the screws holding the cover in place had Loctite or some similar product on them to keep them from vibrating. Small details like this show that the manufacturer has really taken time to make the best possible product. After getting the cover off I found that there was a impressive amount of heatsinks inside. You can also see on top of one of the heatsinks that there is a thermal probe which controls the fans RPM.
This SilenX 400w has pretty standard connections including: 6 Molex, 1 berg, 1 Auxillary, 1 12v, and 1 ATX. None of the cables have sleeving or any other form of cable management which would have been nice to see but is alright none the less. The cables also don't look to be too long which is the case of many other power supplies.
Testing
I installed this SilenX 400w power supply to my normal test bed which is the above hardware. As I suspected the cables are a good length and not too long which is nice. To test the noise level of this power supply I bridged one of the black wires with the green one on the 20 pin connector so I could run it without anything else. After comparing the two power supplies I found that the SilenX 400w was much quieter than the True Silent 450w. I installed the power supply to my computer and hooked everything up. I also took out the temporary video card that I have been using and replaced it with a XFX GeForce FX5700 Ultra that will soon be reviewed. The cables are a not too long but were long enough with some slack to reach down to the Molex on the video card.
# Test Bed: Albatron K8X800 Pro II (review to come)
# AMD Athlon64 3200+ (review to come)
# 60GB Seagate Barracuda IV HDD
# 1024MB PC3200 Corsair TwinX
# XFX GeForceFX 5700 Ultra
In this era of stealth advertising, one must be getting a pretty good bonus at the end of the month for getting a product on the slashdot front page.
(Yes, I'm stealing links from some of my old posts)
http://www.tranquilpc.co.uk/
If you were wondering how much it is and where to order it, go here.
0 dBA may be "perfectly silent" in the sense that you can't hear it by itself, but if you put two or more 0 dBA sources together, you will hear them. The 0 dBA sources are producing sound.
Wrong. Zero dB is just an arbitrary choice and a sound at 0 dB has nonzero amplitude. In air the reference pressure is normally 20 micropascals. The previous poster is correct, the decibel scale is relative, and negative infinity dB is truly silent.
"I believe that the cult of the particular brings only death - for it bases order on likeness." St.-Exupery
The ATX power supply standard has nothing to do with the size of the power supply.
The ATX, and more common ATX12V and EPS12V, refers to the type of connectors supplied as well as a few power requirements that don't concern most home users.
If you are looking for a small 400W ATX12V supply look at either Etasis or a company called SPI, which goes by the name of Sparkle or Zippy at your local Fry's.
A 14 db "silent" PSU is nothing new. There are fan-less PSUs available on the market now if silence is what you want.
For example, the Silent Boost heatsink/fan from Thermaltake is advertised as being as loud as 21 dBA. However, closer inspection will tell you that it uses an 80cm Panaflo 2450 RPM fan, and Panasonic says the fan alone (without the heatsink, which will add to the noise due to additional turbulence) is 28 dBA loud.
The same goes for all sorts of fans and PSUs advertised as being silent. Manufacturers exaggerate their claims, and the one with the lowest number typically sells the loudest product.
Typically the most irritating noises in order are
1) CPU Fan
2) PSU Fan
3) Case Fans
4) HDD
I have a Zalman pure copper Flower on my CPU with only one 12cm fan ducted near it. (No CPU fan). With my HDD decoupled it was silent (i.e. I could not hear it at 2 AM from 1 meter) during normal operation and barely audible when seek/writing.
To overclockers 28dB may seem quiet, but whispers are about 24dB. I personally find it dificult to work with someone whispering 1 meter away. About every 3 dB doubles the acoustic energy. (e.g. if one fan is 20dB, then two of the same fans would be about 23dB) I guestimate my system at about 22 dB.
Tech Report compares the SilenX with four of its competitors here.
I am not impressed. have a look at this NorthQ 400W 12dB or this NorthQ 500W 12dB PSU.
And the best part is, that low frequency vibration will help the motherboard crack even faster since the Zalman coolers all cheerfully ignore the max weight limits set by motherboard companies. They have supposedly caused a few mobo deaths.
Tip- a)make sure all the standoffs are installed properly and the mobo is screwed down. b)if you move the machine, consider taking the CPU heatsink off FIRST, because if you bounce it around, the heft of the heatsink could flex the motherboard a little too much.
Please help metamoderate.
Silent PC Review is a good site for finding out about quiet components. According to their ratings on power supplies, there are actually a few 400 watt PSU's that they ranked better than this one:p =modlo ad&name=Sections&file=index&req=viewarticle&artid= 28&page=2
http://www.silentpcreview.com/modules.php?o
These things are neat. No fan, just a big-ass heatsink sticking out the back of your case. But remember that without the airflow from the PSU you will need a fan for your case (or a special self-cooling case).
Serve Gonk.
Zalman, Thermaltake and others neglect to specify this, which is no surprise since their claims always clash with each other and with their suppliers'.
And there's also the subjective side of things, but that's a whole other issue. Two fans with the same noise emission levels aren't necessarily as pleasant, since their spectra may be completely different. Reducing RPMs will give you less overall noise, but crappier fans will always give you irritating bearing noise, for instance, even though they may be quiet on average.
I know I'm not the OP, but I just built a new PC last week using Zalman stuff, so I can answer some of it. I bought two Zalman 80mm Quiet Mode fans for $9.98 and the Zalman Copper - Aluminum CPU Cooler for $35.99. The CPU fan is very quiet, and the 80mm fans are quiet at around the 1700 - 1900 rpm range (but loud at 3000 rpm). The quiet mode the 80mm fans speak of is simply an adapter with a resistor to drop the current. I didn't even install it, rather I let the BIOS control the fan speed. I can't speak of the Zalman PSU since I went with Antec (which is rather loud, but pretty).
Aych tea tea pea colon slash slash slash dot dot org slash
You are wrong. 0dB means a unity gain. In other words, the signal you are measuring is exactly the same intensity as the reference signal.
In audio, 0dBA (notice the A) means it's the same intensity as the smallest discernible noise to "standard" human ears. Basically it's pretty damn quiet.
You most certainly can have negative dB. It just means attenuation (ie, the signal you are measuring has less intensity than the reference signal). 0 gain (which would be truly silent) is the same as negative infinity dB.
Your stereo achieves maximum volume at OdB because at that setting there is 0dB of attentuation applied to the signal before it gets to the gain stage(s). The numbers on a stereo, or mixing board (well, the numbers below unity at least) really ought to be specified at -XdB not XdB. So when set to 15dB, your stereo is attenuating the signal by 15dB before passing it to the gain stage.
Sound Pressure Levels (SPL), on the other hand are the measured SPL compared to a reference level defined to be 0dB. 0dB is defined to the the standardized lower limit of human hearing under ideal conditions. Interestingly, for humans with no hearing loss, this lower threshold is thermally limited. In other words, if your hearing isn't damaged and there are no other sounds, you can hear the temperature of the room. At 0dB, your eardrum is deflecting by about the diameter of a Hydrogen atom. Another fun fact to know and tell: the system of small bones that convey the vibration from the ear drum to the inner ear function as a hydraulic system with a 7000:1 ratio, which is almost exactly the accoustic impedance mismatch between air and the fluid in your inner ear. For an intersting discussion of human hearing, read the first few chapters of Master Handbook of Acoustics
Being able to hear the TV is just a matter of having good (not alien, just good) hearing.
The scanline transducer operates 525 times per refresh, 30 times a second: 15.750khz. This is within the range of human hearing, so if a transducer is of poor quality, you can hear it.
My guess is that many people just don't pay attention to it, even though they can hear it.
However lots of people who grew up listening to Walkmans and other devices can't hear it, because they've destroyed their high-range hearing.
I recently bought a silent Nexus power supply. Ran me $70. It's silent, looks very cool, and to boot the fan actually blows across the CPU. The back of the PS (the part when you put the plug into) is a mesh instead of solid metal, so the airflow is quite effective.
YMMV
"If at first you don't succeed, lower your standards."