Efficiency, Differential Temperature and Noise
Efficiency is defined by the power output divided by the power input and is usually expressed as a percentage. If a PSU were a 100% efficient (which none are) 600 watts of AC power going in would result in 600 watts of DC power coming out (with no waste heat to dissipate). In the real world there are always inefficiencies and power is lost in the form of heat during the conversion process. Newer revisions to the ATX12V Power Supply Design Guide V 2.2 have continued to increase the efficiency recommendations for PC switching mode power supplies and now lists both required and recommended minimum efficiencies.
We measured the AC power input to the SX600-G PSU with an Extech power analyzer while the total DC load was found by adding all the individual +3.3V, +5V, +12V, -12V and +5VSB loads together.
The overall efficiency of the SX600-G SFX power supply is very good and easily meets the criteria for 80 Plus Gold certification, even while operating on 115 VAC and at elevated temperatures.
80 Plus Program
Note: Tests conducted at room temperature (25°C)
Differential Temperature and Noise Levels
To simulate real world operation, some of the warm exhaust air from the PSU under test is recirculated back to the intake through a passive air duct, which allows the PSU air inlet temperature to increase with load, just like it would in a real PC.
The differential temperature across the power supply was calculated by subtracting the internal case air temperature (T in) from the temperature of the warm exhaust air flowing out the back of the power supply (T out).
Thermocouples were placed at the air inlet and exhaust outlet. The ambient room air temperature was 23ºC (74ºF) +/- 0.5ºC during testing.
T out = temperature of air exhausting from power supply
T in = temperature of air entering power supply
Delta T = T out – T in
Sound pressure level readings were taken 3’ away from the rear of the case in an otherwise quiet room. The ambient noise level was ~28 dBA.
The SilverStone SX600-G SFX power supply features an “intelligent semi-fanless” fan speed control circuit, which is supposed to turn the fan off at low power for silent operation. During testing, the fan turned on as soon as we applied power (23°C room temperature) and stayed spinning during all of our tests. However, the fan was very quiet (virtually silent at low to mid power) and did not become noticeable until Test #4 at 450W. At full load the fan speed had increased to where it was very noticeable.
(Courtesy of SilverStone)
I am building a mITX PC at
I am building a mITX PC at the moment, and liked the size, design and layout of a lot of Silverstone’s SUGO and MILO cases, but most take SFX PSUs. The price for a SFX PSU is hard to justify. I ended up with a SG08-LITE because it takes ATX PSUs, and got a Corsair CX600M for $54, vs the $130 Silverstone SX600-G.
That is a tradeoff with
That is a tradeoff with smaller builds, you get the convenience of a physically smaller computer and the advantages of that, but the build is often more involved, and the price has a premium. It sounds like you weighed those pros and cons and went with something that would fit your needs. That being said, if you didn’t need 600 watts, and most single GPU systems won’t even come close to that, the Silverstone ST55F-G 550 watt is $115, and the ST45SF 450 watt is $80. That is not a terrible price premium for a quality PSU.
Well i do own one of these
Well i do own one of these and i got to say:
Yes it is expensive but it uses high quality components and its the only 600W SFX PSU out there.
If other manufactures would build more SFX PSUs, Silverstone might drop prices.
The number of mini-ITX cases
The number of mini-ITX cases has increased lately, so maybe more companies will start making SFX power supplies. Nexus used to make short (125 mm) ATX power supplies, but not any more. I wish Seasonic would build an SFX power supply.
The new SX500-LG power supply, a 500 W SFX-L unit, has been posted on the Silverstone site, but it has not started to ship yet. Hopefully the extra 30 mm of length that allows the use of a 120 mm fan will result in a quieter power supply that is still very small.
Nice, this might allow me to
Nice, this might allow me to use the flex hard drive bays from my Caselabs M8 with my M3. Technically they fit, but with a normal size PSU, you can’t plug in the drives since they’re too close to the PSU.
I have this power supply and
I have this power supply and it works well but I do have a high pitch squeeling noise coming from it when the computer isn’t powered on. its a bit annoying.
Is this the 430w or 600w
Is this the 430w or 600w version? and when did you buy it?
got same problem…
got same problem…
I don’t notice any noises
I don’t notice any noises coming from mine.
I went for this over the 600w because it had the nice cables included.
Expensive power supply but not much competition. Modular was handy because it meant I could plug in to the motherboard first and also didn’t need to use the peripherals cable.
*the 600w over the 450….
*the 600w over the 450….
It’s a bit of a shame they
It’s a bit of a shame they have a nice black PSU, then include a boring plain metal adapter plate for ATX in it… looks nasty in a black case.