DC Load Regulation and AC Ripple
Establishing an accurate load is critical to testing and evaluating a PC power supply. PCPerspective’s power supply test bench can place a precise DC load on the PSU under test. Each power supply is tested under controlled, demanding conditions up to its maximum rated load (at 40ºC). Our current suite of tests includes:
• DC Load Regulation
• AC Ripple and Noise
• Differential Temperature
The Corsair SF Series 600W power supply was evaluated on both features and performance. A full range of equipment was used to test the power supply under controlled load conditions.
• (2) CSI3710A Programmable DC load (+3.3V and +5V outputs)
• (4) CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4)
• (2) 200W Precision resistor load bank (+12V5 and +12V6)
• Switchable precision resistor load bank (-12V and +5VSB)
• Agilent 34401A digital multimeter (Accuracy ±0.0035% vDC)
• Extech 380803 Power Analyzer (Accuracy ±0.5% of full scale)
• DS1M12 "StingRay" digital oscilloscope (20M S/s with 12 Bit ADC)
• Powerstat Variable Autotransformer, 1.4 KVA, 0-140 VAC
• Extech Model 407738 digital sound level meter (Accuracy ±1.5 dB)
The following cables/connectors were used to connect the power supply to the PCPerspective power supply test equipment.
• (1) 20+4 pin ATX
• (1) 8-pin EPS/ATX12V
• (2) 6-pin PCI-E
• (2) SATA
• (2) Molex
DC Output Load Regulation
To simulate demanding and maximum loading conditions, the SF600W power supply was connected to the load testers and supplied with a constant 120 VAC. In this test we are interested in seeing how well a PSU can maintain the various output voltages while operating under different loads.
The ATX12V V2.2 tolerance for voltages states how much each output (rail) is allowed to fluctuate and has tighter tolerances now for the +12V outputs. We have included a second table of expanded tolerances (±1% to ±6%) for reference.
The following tables list the DC voltage results for the SF Series 600W PSU while operating on 120 VAC, 60 Hz.
The power supply produced excellent voltage regulation on all of the DC outputs with the three main rails staying within ±2% of the recommended ATX guidelines; very good.
AC Ripple and Noise on the DC Outputs
The amount of AC ripple and noise present on the DC outputs was checked using a digital oscilloscope. This AC component may be present in the KHz range where most switching power supplies operate or it may be more prevalent at the 60 Hz line frequency. We adjust the O-scope time base to look for AC ripple at both low and high frequencies. The ATX12V V2.2 specification for DC output noise/ripple is defined in the ATX12V Power Supply Design Guide.
Ideally we would like to see no AC ripple (repetitive) or noise (random) on the DC outputs – the cleaner the better! But in reality there will always be some present. I measured the amplitude of the AC signal (in millivolts, peak-to-peak) to see how well the power supply complied with the ATX standard. The following table lists the ripple/noise results during all of the load tests for the main output voltages of interest.
The SF600 power also exhibited excellent AC ripple and noise suppression with the results staying far below the ATX recommended guidelines, even at full load.
It can NOT be used in
It can NOT be used in standard ATX cases because the cables are too short!
Number 1. He means cases that
Number 1. He means cases that use “standard” ATX power supplies. Number 2. Obviously you wouldn’t use this in a full sized tower like a Corsair 900D. And why would you? Number 3. You can purchase longer cables and/or extensions if you had to. A small ps like this is more than likely going to be used in a smaller environment. What would be the point of putting this into a mid or full sized ATX environment? None.
Watercooling in a midtower
Watercooling in a midtower maybe? I have one sf600 in a itx environment but i was asking myself the same question. The only answer i found is more room for water pumps/ watercooling tubes in a atx/itx case.
Per example: the fractal
Per example: the fractal design nano S/ phanteks evolv itx cases are on the big size of itx case and they do support normal atx PSU but a SFX psu like the sf600 could make the difference in the watercooling space of somebody
At the moment there’s no
At the moment there’s no longer cables for the sf600, BTW don’t tell people to get longer cables, they are different, in many ways ,and can ruin a system. thanks
The picture supplied by
The picture supplied by Corsair labeling what the parts are matches my SF450 PS. #16 uses blue colored caps versus the red shown for SF600, is all i can see is different.
I’ve got the 450 watt running
I’ve got the 450 watt running in an unRAID server build. Powering 6 drives and I can’t say I’ve ever seen the fan come on. I had to order a separate bracket to fit in the case though. Even though the case will only fit an mITX motherboard and barely anything else, the cut out is for a full size ATX PSU. Case is a Lian-Li Q25B. Awesome little case for a NAS box or anything along those lines.
If these had been around when
If these had been around when I built my HTPC, I’d probably have stuck a 450W in there. Instead, I ended up with the Silverstone SFX-L 500W – not bad at all, but inside of a Fractal Node 304 you take all the extra space you can get. Also, these seem to perform admirably. Good to see Corsair making an effort when they only have a single SFX line (although Platinum or Titanium efficiency would be even better, of course).