SilverStone Strider Platinum ST1000-PTS Power Supply Review

1000W of stable power with high efficiency in a compact enclosure

SilverStone recently introduced two new compact, high-output models to their Strider Platinum Series, the ST1000-PTS and the ST1200-PTS, which feature a small chassis that measures only 140mm (5.5”) deep. The Strider Platinum Series is one of SilverStone’s most complete lines. Starting at 550W and going up to 1200W, the Strider Platinum Series includes eight different models, six featuring a compact chassis. Two legacy models, the ST1000-PT and ST1200-PT forgo the small enclosure and use a larger 140mm fan. In addition to their small size the SilverStone Strider Platinum power supplies come with fully modular cables and stay relatively quiet through mid-power operation.

SilverStone Strider Platinum Series ST1000-PTS Key Features:

• 1000W DC power output
• High efficiency with 80 Plus Platinum certification
• 100% Modular cables
• Quiet 120mm cooling fan with FF122 dust filter
• 24/7 Continuous power output with 40°C operating temperature
• Strict ±3% voltage regulation and low AC ripple
• Dedicated single +12V rail (83A/996W)
• Universal AC input (90-264V) with Active PFC
• DC Output protections: OPP, OCP, OVP, OTP, UVP, and SCP
• Dimensions: 150mm (W) x 86mm (H) x 140mm (L)
• 5-Year warranty
• Around $230 street price

Specifications

The SilverStone Platinum Series 1000W power supply is rated for a combined, continuous output power of 1000 watts at 40°C. The PSU incorporates a single +12V rail that can deliver up to 83A/996W.  The PSU includes universal AC line input (automatically adjusts the AC line voltage) and active PFC, which makes the unit more environmentally friendly to the local power grid.

SilverStone ST1000-PT PSU Specifications: (from the SilverStone website)

Packaging and Parts

The ST1000-PTS power supply arrived packed inside a standard retail box showcasing the unit’s features and specifications. 

In addition to the power supply, the box contains a heavy duty power cord (3x14AWG), mounting screws and thumb screws, a User’s Guide, Product Manual, wire ties, cable ties, SilverStone FF122 dust filter, and a large bundle of modular cables.

Eleven flat ribbon-style modular cables handle the power distribution. See the specifications table above for connector count and lengths. All of the modular cables are flat ribbon-style to assist with neat cable routing and to help maximize airflow.

A Detailed Look

The SilverStone Platinum Series 1000W power supply enclosure is painted matte black and measures 140mm (5.5”) deep.  The back panel includes an AC receptacle, master power On-Off switch and an open honey-comb grill for good airflow.

The power supply uses a Yate Loon Electronics 120mm fan for cooling.  The fan (D12SH-12) is rated for 0.30A and 1800 rpm at 12 VDC and features a hybrid ceramic sleeve bearing. Included with the power supply is one of SilverStone’s FF122 fan filters. The 120mm square dust filter incorporates magnets in the frame to hold it in place on steel chassis or it can be attached with screws.

The front panel on the 1000W PSU incorporates eleven modular cable connectors, all nicely labelled and color coded. The power supply comes with little plastic covers over most of the connectors. During installation, you can just uncover the connectors you need and leave any unused connectors covered for a clean look.

Removing the chassis cover yields a good look at the layout and components inside the ST1000-PTS power supply.  SilverStone is using Enhance Electronics as the OEM for the Platinum Series. The overall layout, soldering, and build quality all look very good.

The power supply features a modern full bridge resonant LLC circuit design to deliver very high efficiency along with synchronous rectification on the secondary with DC-to-DC converters to produce the +3.3V and +5V rails from the +12V output.

All of capacitors used inside the PSU are high-quality with a good mix of electrolytic and solid polymer caps used throughout (Nippon Chemi-con, Suncon, and CapXon). For example, the two main primary bulk capacitors are made by Nippon Chemi-Con (KMW) and rated for 560uF, 450V and 105°C.

Testing Methodology

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
• Efficiency
• Differential Temperature
• Noise

The SilverStone Platinum ST1000-PTS 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
• (2) 8-pin EPS/ATX12V
• (8) 6-pin PCI-E
• (6) SATA
• (6) Molex

DC Output Load Regulation

To simulate demanding and maximum loading conditions, the ST1000-PTS 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 SilverStone Platinum Series ST1000-PTS power supply while operating on 120 VAC, 60 Hz.

The power supply produced very good voltage regulation on all of the DC outputs with the three main rails staying easily within ±2% of the recommended ATX guidelines; well within SilverStone’s claimed ±3%.

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 ST1000-PTS power supply exhibited good AC ripple and noise suppression with the results staying far below the ATX recommended guidelines, even at full load when delivering a 1000W to the DC outputs.

Efficiency

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) 1000 watts of AC power going in would result in 1000 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 ST1000-PTS 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 SilverStone ST1000-PTS power supply produced excellent efficiency, easily meeting the 80 Plus Organization Platinum criteria, even when operating on 120VAC and at elevated temperatures.

80 Plus Program

Differential Temperature and Noise Levels

To simulate a demanding environment, 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, up to 40°C. 

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 ~27 dBA.

The ST1000-PTS Platinum Series power supply started out very quiet and stayed relatively quiet through the mid-power range. At full load with an elevated ambient temperature, the cooling fan did speed up and the noise became very noticeable but I was not able to take SPL readings because of all the DC load cooling fans cycling on and off in the background.

SilverStone ST1000-PTS Platinum Series Fan Speed

Final Thoughts and Conclusions

The new compact chassis SilverStone Strider Platinum Series ST1000-PTS power supply performed very well during our testing. We found the overall efficiency of the power supply to be excellent and easily meets the rigorous 80 Plus Platinum criteria for high efficiency, even while operating on 120 VAC and at elevated temperatures.

The voltage regulation delivered by the ST1000-PTS is very good across the board. All of the main DC outputs stayed well within SilverStone’s claimed ±3% range with the three primary rails measuring ±2%. AC ripple and noise suppression was also good. The power supply is very quiet at low power levels and remains relatively quiet through mid-power operation. Only at the full 100% load did the fan noise really become noticeable. The ST1000-PTS comes with a good assortment of all-modular, ribbon-style cables with two ATX12V 4+4 pin/EPS 8-pin, and eight PCI-E connectors for multiple graphic card support. Unfortunately, none of the PCI-E connectors are on a single dedicated cable, they are all two per cable. And last but not least, the PT1000-PTS power supply comes with a full suite of protection circuits and is backed by a five year warranty.

We only have two minor complaints with the ST1000-PTS. First we would like to see a little higher max operating temperature than 40°C (like 45°C or 50°C) especially for a densely packed, compact chassis. Second, while the ST1000-PTS comes with eight PCI-E connectors, there are not any dedicated cable/connectors – only two connectors, daisy-changed, per cable. Neither of these issues is a show stopper.

At the time of this writing (September 2019), the ST1000-PTS and ST1200-PTS are still somewhat hard to find, so the price is relatively high. The SilverStone ST1000-PTS is currently selling around $230 at retailers such as Amazon and Newegg. We expect to see the selling prices come down as availability goes up.

Strengths:

• 1000W continuous DC output in a compact ATX chassis
• Excellent efficiency (80 Plus Platinum certified)
• Very good voltage regulation (±2% confirmed)
• Clean DC outputs with relatively low AC ripple/noise
• Very quiet operation below ~60% load
• All-modular cable design with flat ribbon-style cables
• DC Output protections: OPP, OCP, OVP, OTP, UVP, and SCP
• Universal AC input with Active PFC
• 5-Year warranty

Minor Weaknesses:

• Max operating temperature is 40°C
• Two PCI-E connectors per cable (no dedicated cable/connectors)

I would like to thank our friends at SilverStone for sending us the Platinum Series 1000W PSU to review – thank you!