Seasonic Snow Silent 1050W PSU Review (XP3)

Today we look at the latest power supply from Seasonic - just in time for Christmas! Their festive looking 'Snow Silent' power supply is fully modular, with 80 Plus Platinum certification. Seasonic have incorporated a new low noise fluid dynamic bearing fan along with a rather eye catching white paint job. They are in stock now at Overclockers UK for £199.99 - but is it worth the money? Seasonic have earned a valued reputation in the enthusiast market, and rightly so - they have been one of the most consistent manufacturers of power supplies in our tests over the last 3 years. This is the first 'white' coloured Seasonic power supply we have reviewed, so if you have a matching chassis with a windowed panel, it will undoubtedly look great with some white LED lighting behind it. Seasonic stand behind this unit with a full 7 year warranty, for peace of mind. Snow Silent Overview: 80PLUS® Platinum Certified Super High Efficiency DC Connector Panel with Integrated VRM [Voltage Regulator Module] DC to DC Converter Design Dual Copper Bars Active Power Factor Correction [99% PF Typical] Conductive Polymer Aluminum Solid Capacitors Highly Reliable 105°C Japanese Aluminum Electrolytic Capacitors Gold Plated High Current Terminals Ultra Tight Voltage Regulation High +12V Output Dual Sided PCB Layout Seasonic Patented Hybrid Silent Fan Control Ultra Ventilation [Honeycomb Structure] Full Modular Cabling Design Multi-GPU Technology Support All-in-One DC Cabling Design Easy Swap Connector Universal AC Input [Full Range] 7 Years Warranty Nothing fancy - the Seasonic Snow Silent 1050W is shipped in a rather understated white box, with a small image of the product bottom right. Inside, the power supply is protected between two thick foam panels. The cables are all stored in a cardboard box at one side. The power supply is also protected inside a soft, white, felt bag. A little reference sheet is included giving a recommendation for cable power connection to graphics cards. Basically if you are using a graphics card which takes more than 225watts under load then use two separate PCIe power cables rather than two headers on a single cable. Seasonic include some thick felt ties, some plastic ties, a regional specific power cable and a user manual. There are also some mounting screws for the system build. The main motherboard power cable is sleeved, however all other cables are the flat 'ribbon' style, which proves popular with system builders who have to route a plethora of cables behind a motherboard tray. The quality of all the cables is excellent. Cable Connectors MB 20+4 pin x1 (590mm) CPU 4+4 pin x1 (650mm) CPU 8 pin x1 (650mm) PCI E 8 pin (6 pin +2) x8 (600mm) SATA x12 (530mm+150mm+150mm) SATA x2 (530mm+150mm) MOLEX x3 (550mm+150mm+150mm) MOLEX x2 (350mm+150mm) The cables are all high grade flat ribbon style to help with the routing phase of the system build. The main MB 20+4 cable is sleeved. There are a total of 14 SATA connectors, meaning this power supply is also ideal for a massive storage server system. Those running a high end SLi or Crossfire rig will be happy to note a total of eight 6+2 pin PCI e connectors. We like the appearance of the Seasonic Snow Silent 1050W unit. Not often we get to see a white power supply, so they always attract the eye. The 'Snow Silent' letters are actually black and silver. There is a little silver accent (line) running across, and upwards on the side panels. These are stuck onto the side panels. We received one of the early review samples, and the silver sticker had torn a little. We do handle them fairly roughly during testing, but we hope these are stuck a little better to the side panels on retail samples. Paint quality is high, and it passed our screwdriver test. This involves running the head of a Philips head driver down the side of the chassis with light to medium force. After all, how many times have you accidentally connected with a power supply during a system build? Even if the power supply did scratch however, it is silver underneath so its actually almost invisible against the white paint - unless you study closely. The Snow Silent measures 190 mm x 150 mm x 86 mm (LxWxH). A large white (cream almost) fan is visible behind the grill. We will take a closer look at the fan when we open up the housing for a peak inside. The modular panel is laid out in an easy to understand manner, with the main motherboard power connector top left. There is a fan control switch which alternates between normal and 'hybrid' modes. The CPU and PCI-e connectors stretch across the bottom row, underneath the peripheral headers. The other end of the power supply is vented, with a power connector and switch at the side. Above, we can see the specifications of the power supply. Seasonic class this as an XP3 model - the same number as the Seasonic Platinum 1050WXP3 that we reviewed back in August this year. Seasonic Snow Silent 1050W (XP3) DC Output +3.3V +5V +12V -12V +5Vsb Max Output 25A 25A 87A 0.5A 3A Total Power 125W 1044W 6W 15W 1050W This power supply can deliver 87A on the +12V rail. Plenty of power for even the most demanding Crossfire and SLi configurations. It is worth noting that this is increased from 83A on the older Platinum 1000W model we reviewed back in May 2012. Seasonic have opted for a Ong Hua 120mm fan, Model number HA1225H12F-Z. This is a high grade Fluid Dynamic Bearing (FDB) fan designed for low noise emissions. These fans not only tend to emit lower noise levels, but they are rated to last longer as well due to the lubrication of the bearing itself. The Seasonic XP3 design is rock solid and this isn't the first time we have looked at it. It also featured in the Cooler Master V1200 Platinum power supply which we reviewed earlier this year. Soldering quality is excellent throughout. Behind the AC receptable is a sealed PCB which is home to some of the components of the EMI filter – a single X cap, four Y caps and a CM choke. The other components of the filtering stage are on the main PCB, which include an MOV, two pairs of Y and X Caps and two more CM chokes. The primary side is a full bridge design with an LLC converter for lossless switching. The secondary side uses a synchronous design with +12V fets on the main PCB. The DC-DC converters are installed on the modular PCB to help reduce power loss. The main PCB and modular PCB incorporate high grade Japanese electrolytic and solid capacitors. Seasonic are using three high grade Japanese capacitors on the primary stage (class leading ‘Nippon Chemi Con’). These are all 105c rated. All three are rated 330uF 420V. The Seasonic Platinum 1200W unit uses three more powerful 390uF rated capacitors in the primary stage, for those interested. On this page we present some high resolution images of the product taken in our professional studio. These will take much longer to open due to the dimensions, especially on slower connections. If you use these pictures on another site or publication, please credit Kitguru.net as the owner/source. Additional technical assistance: Peter McFarland and Jeremy Price. Correctly testing power supplies is a complex procedure and KitGuru have configured a test bench which can deliver up to a 2,000 watt DC load. Due to public requests we have changed our temperature settings – previously we rated with ambient temperatures at 25C, we have increased ambient temperatures by 10c (to 35c) in our environment to greater reflect warmer internal chassis conditions. We use combinations of the following hardware: • SunMoon SM-268 • CSI3710A Programmable DC load (+3.3V and +5V outputs) • CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4) • Extech Power Analyzer • Extech MultiMaster MM570 digital multimeter • SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) • Digital oscilloscope (20M S/s with 12 Bit ADC) • Variable Autotransformer, 1.4 KVA We test the power supply with the fan in the ‘normal’ state. DC Output Load Regulation Combined DC Load +3.3V +5V +12V +5VSB -12V A V A V A V A V A V 100W 1.54 3.34 1.76 5.07 6.65 12.12 0.50 5.01 0.20 -12.03 200W 3.13 3.34 3.50 5.07 13.50 12.12 1.00 5.01 0.20 -12.03 400W 6.40 3.34 7.05 5.07 27.50 12.12 1.50 5.00 0.30 -12.04 600W 9.82 3.33 10.75 5.05 41.70 12.10 2.00 5.00 0.30 -12.03 800W 13.27 3.33 14.56 5.05 56.40 12.08 2.50 4.99 0.50 -12.04 1050W 16.55 3.33 15.75 5.05 74.00 12.08 3.00 4.99 0.60 -12.03 Load regulation is fantastic with all the rails holding tight, within 1.5%. Seasonic Snow Silent 1050W PSU Maximum Load 1205W We managed to get another 155W from the power supply before the protection circuitry kicked in. The supply was undamaged and it was ready to fire up again when we dropped the load to a more realistic level. Next we want to try Cross Loading. This basically means loads which are not balanced. If a PC for instance needs 500W on the +12V outputs but something like 30W via the combined 3.3V and +5V outputs then the voltage regulation can fluctuate badly. Cross Load Testing +3.3V +5V +12V -12V +5VSB A V A V A V A V A V 885W 2.0 3.33 2.0 5.03 72.0 12.08 0.2 -12.02 0.50 5.01 240W 20.0 3.33 24.0 5.03 2.0 12.09 0.2 -12.03 0.50 5.01 The Seasonic Snow Silent 1050W power supply delivered a great set of results in the demanding Cross load test, as shown above. We then used an oscilloscope to measure AC ripple and noise present on the DC outputs. We set the oscilloscope time base to check for AC ripple at both high and low ends of the spectrum. ATX12V V2.2 specification for DC output ripple and noise is defined in the ATX 12V power supply design guide. ATX12V Ver 2.2 Noise/Ripple Tolerance Output Ripple (mV p-p) +3.3V 50 +5V 50 +12V1 120 +12V2 120 -12V 120 +5VSB 50 Obviously when measuring AC noise and ripple on the DC outputs the cleaner (less recorded) means we have a better end result. We measured this AC signal amplitude to see how closely the unit complied with the ATX standard. AC Ripple (mV p-p) DC Load +3.3V +5V +12V 5VSB 100W 10 10 15 5 200W 15 10 15 10 400W 15 10 20 10 600W 15 15 20 15 800W 15 15 25 15 1050W 15 20 30 15 Ripple suppression is very good. All of the rails exhibit very low ripple and the +12v rail for instance peaks at 30mV, well within the rated specifications. Efficiency (%) 100W 85.7 200W 88.6 300W 93.3 500W 94.5 800W 93.3 1050W 92.3 The overall efficiency results are excellent, peaking at 94.5% at 500W. This drops close to 92% efficiency at full load, a very impressive result. We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components. Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635. Today to test the Power Supply we have taken it into our acoustics room environment and have set our SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) one meter away from the unit. We have no other fans running so we can effectively measure just the noise from the unit itself. As this can be a little confusing for people, here are various dBa ratings in with real world situations to help describe the various levels. KitGuru noise guide 10dBA - Normal Breathing/Rustling Leaves 20-25dBA – Whisper 30dBA - High Quality Computer fan 40dBA - A Bubbling Brook, or a Refrigerator 50dBA - Normal Conversation 60dBA - Laughter 70dBA - Vacuum Cleaner or Hairdryer 80dBA - City Traffic or a Garbage Disposal 90dBA - Motorcycle or Lawnmower 100dBA - MP3 Player at maximum output 110dBA - Orchestra 120dBA - Front row rock concert/Jet Engine 130dBA - Threshold of Pain 140dBA - Military Jet takeoff/Gunshot (close range) 160dBA - Instant Perforation of eardrum Noise (dBA) 100W 28.0 200W 28.0 400W 28.8 600W 30.5 800W 32.4 1050W 33.7 The 120mm fan in the Snow Silent 1050W performs exceptionally well, hitting 33.7dBa under full load. Most of the time the power supply is barely audible. It is only after 800watts is demanded that the fan can be heard - not a realistic situation for many running this system. We would recommend a 1250W rated power supply if you need a constant 800-1000watt demand. Temperature (c) Intake Exhaust 100W 35 37 200W 35 40 400W 37 42 650W 43 52 800W 45 54 1050W 47 60 Temperatures are well controlled thanks to the efficiency of the unit. The fan spins slow most of the time, only spinning up in the last 20% of load. Maximum load Efficiency 1205W 91.4 Pushing the power supply above its rated limits generates an efficiency level of around 91.4%. This is not a viable ‘real world’ situation, but its interesting nonetheless. The Seasonic Snow Silent 1050W Power Supply is certainly eye catching. The white paint, subtle branding and silver accenting is attractive. The enthusiast audience using a windowed LED lit white case from the likes of Corsair or NZXT will find this unit particularly appealing. Technically, the Seasonic XP3 design has been proven bulletproof in 2014 and the new Snow Silent model is no exception. Seasonic don't skimp on the internal components, opting for highest grade Japanese grade 105c rated Nippon Chemi Con capacitors. This unit adopts a new Fluid Dynamic Bearing 120mm fan for quiet operation. In the real world the power supply is very quiet, right up until a full 800watts is demanded. The fan starts to actively spin to compensate for rising temperatures. That said, even at a 1000 watt load it remains reasonably quiet. Realistically we would recommend if you need a constant 800-1000 watts that you budget for a 1200w or 1250w unit. Ideally you want to be running between 40-70 percent load to achieve excellent efficiency and cooler running temperatures. The Seasonic Snow Silent 1050W uses three Nippon Chemi Con 105c 330uF 420V capacitors and in our tests it was actually able to deliver 1,200Watts of power before shutting down. This is a remarkable result and bodes well if you are running close to the 1000W redline under load. Seasonic are clearly over specifiying these units which is commendable, especially as we often see corners being cut by competitors. Technically, these high grade Platinum units from Seasonic are class leaders. Load regulation is stellar, ripple suppression is excellent and the unit copes well with demanding cross load tests. You can pick up the Seasonic Snow Silent 1050W power Supply from Overclockers UK for £199.99 inc vat. It is an expensive unit, but if you are powering a high level multi GPU system then it would be uneducated to skimp on the quality of the power delivery. Discuss on our Facebook page, over HERE. Pros: built to the highest standards. Nippon Chemi Con 105c rated primary capacitors pure modular design. hysteresis system works great. low noise fluid dynamic bearing fan. 8 PCIe connectors and 14 SATA connectors. 7 year warranty. Cons: Silver stickers didn't seem adhered too well on our sample unit. Kitguru says: Another stellar high grade power supply from the Seasonic team. We think it looks great in white too!