Enermax Platimax 850w Power Supply Review (EPM850EWT)

When shopping for a quality power supply Enermax are always one of the companies to place at the top of a shortlist. Last October we looked at their Platimax 1200W power supply and today we are reviewing the 850W version. Like the bigger brother, this product is 80 Plus Platinum Certified. The Platimax has been released as a replacement for the MaxRevo range of products and is a Dynamic Hybrid Transformer Topology, which according to Enermax is a "Technological breakthrough topology using a staged dynamic transformer array for extremely high efficiency with the most durable and stable output at any load." Efficiency for these units is rated between 90 and 94 percent, meeting 80 Plus Platinum ratings. Unlike the 1200W model which we previously reviewed, this model isn't a fully modular design. It is compliant with SSI PSDG for the latest Intel and AMD processors and is downward compatible with EPS12V v2.92, v2.8. All of the units in this range feature a 13.9cm Enermax fan with Twister Bearing Technology. Specifications and product overview: 80 PLUS® Platinum 90 to 94 percent efficiency at 230V and 20 to 100 percent load. 80 PLUS® Platinum certified. Dynamic Hybrid Transformer Topology Technological breakthrough topology using a staged dynamic transformer array for extremely high efficiency with the most durable and stable output at any load. ErP Lot 6 ready! Help systems to meet EU eco-design directive ErP/EuP Lot 6 (<1W in standby mode) due to improved, high-efficient 5V standby (+5Vsb) circuitry. C6 & Hybrid Support Supports energy saving modes of current and future CPU & GPU generations (C6 & Hybrid Mode) due to ZERO LOAD Design (no minimum load). Multi Rail Design Stable and safe power supply thanks to up to six high-performance and massive 12V rails each with separated over current protection (OCP). Extremely low ripple noise. Future ready and flexible All-round modular cable management. 10/12P sockets for possible connector changes of upcoming high-performance CPU and graphics card generations. Intel ATX12V v2.3 Compliant with latest desktop power supply design guide. Full support of most current CPU: Intel® Core 2 Duo / Quad / Extreme / Core i7 / i5 / i3, “Sandy Bridge“ and AMD Athlon II X2 / X3 / X4 Phenom II X2 / X3 / X4 / X6, “Bulldozer“ or “Llano“. Fit4Server Compliant with SSI PSDG for the new Intel Core Extreme/i7, Xeon and AMD® Opteron and downward compatible with EPS12V v2.92, v2.8. DXXI ready! Full support of most current DX11 graphics cards due to minimum two 6+2P (8P) PCI-E connectors. Full graphics power Supports SLI and CrossFireX systems. Air Cooling by Enermax Integrated 13.9cm fan with patented Twister Bearing Technology ensures efficient and ultra silent cooling and long lifetime (100,000 hours MTBF). SpeedGuard Path-breaking and leading fan speed control to ensure effective and silent cooling. Unmatched 300 to max. 1,000 RPM. HeatGuard Keeping PSU fan running for 30-60 seconds after shut down to dissipate the remaining system heat and prolonging system lifetime. SafeGuard Industry-leading multiple protection circuitry of OCP, OVP, DC UVP, OPP, OTP, SCP & SIP. CordGuard Fixing the AC cord tightly to avoid accidental shutdowns of your PC. Non-stop @ 50°C Non-Stop industrial class performance at 50°C ambient. High-quality Japanese Capacitors Highest Enermax quality standards for leading stability and maximum durability. 105°C Japanese electrolytic capacitors without exception. ENERGY STAR 5.0 ready! Support computer system to meet ENERGY STAR 5.0 standard. Warranty 5 years vendor warranty The Platimax box design and colouring is based around the platinum branding and colour scheme, associated with the 80 Plus Certification process. Inside, the power supply is positioned in the middle of a cutout cardboard panel. Inside is a user manual, cable tidies, a region specific power cable, mounting screws and a bag of modular cables. The Platimax 850W isn't a pure modular design. The images above show the modular cables (left) and the hardwired cables (right). Cabling is high quality 18 AWG sleeved. The main motherboard cable is 16 AWG. We really liked the appearance of the Platimax 1200W power supply and the 850W version is identical, apart from the hardwired cables. The paint surface is rough and textured which feels good in the hand. It doesn't mark easily and is resistant to minor scratches. The power supply measures 150 mm x 86 mm x 175 mm. The Platimax 850W is a very attractively finished product with the logo and name painted on the sides in white. The large 13.9cm fan is clear, although it looks dark from specific angles. This fan uses the excellent Twister Bearing Technology. The fan is rated to spin between 600 rpm and 1,500 rpm. It has an MTBF of 100,000 hours. The power supply is vented to aid air flow. There is a power button and connector next to the vented panel. The modular connectors are well labeled and colour coded for ease of installation. It is foolproof. Specifications highlight a potential 70A available from the six +12V rails. Peak power is rated by Enermax at 930W. This is the same fan that we saw used in the Platimax 1200W version. The 140mm fan is branded EA142512M-0A and is a Twister bearing model. It is rated to 1,500 rpm maximum. The internal build is very clean and there are several rows of thin black heatsinks to separate the components. This is a synchronous design with a DC-DC design in the secondary. The +3.3V and +5V output are produced by two smaller power supply sub divisions which are both connected to the primary +12V rail. This is to ensure the maximum possible efficiency. The Platimax 850W design uses a pair of Rubycon 400v 390 uF capacitors, rated at 105c, which is reassuring to see in a design like this. Enermax are using switching transistors controlled by a CM6901 resonant controller. Enermax are using Japanese Chemi Con electrolytic capacitors to filter the +12V output. The power supply has four +12 rails. Enermax are using a PS232S monitoring circuit which supports under voltage (UVP), over voltage (OVP), and over current (OCP). The cables are fully sleeved into the chassis to protect against long term fraying. On this page we present some super high resolution images of the product taken with the 24.5MP Nikon D3X camera and 24-70mm ED lens. 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 recently – 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 • Extech digital sound level meter • Digital oscilloscope (20M S/s with 12 Bit ADC) • Variable Autotransformer, 1.4 KVA 12V output is combined for our testing. DC Output Load Regulation Combined DC Load +3.3V +5V +12V +5VSB -12V A V A V A V A V A V 100W 1.52 3.37 1.75 5.07 6.63 12.13 0.50 5.04 0.20 -12.17 225W 3.78 3.35 3.82 5.06 15.53 12.11 1.00 5.03 0.20 -12.13 450W 7.52 3.33 8.35 5.05 30.77 12.07 1.50 5.04 0.30 -12.11 675W 11.32 3.32 12.33 5.03 47.54 12.04 2.00 5.00 0.50 -12.07 850W 1.45 3.30 1.17 5.01 63.45 12.00 0.50 4.99 0.20 -12.04 The Enermax Platimax 850W produces strong load regulation across all output. They all achieved between +/-3% of the nominal voltage instead of the recommended +/-5%. Enermax Platimax 850w Maximum Load 972W We managed to get the PSU to achieve 972W before it would shut down, delivering around 122W more than the rated specifications. 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 760W 1.0 3.38 1.0 5.04 60.0 11.98 0.2 -12.05 0.50 5.00 165W 15.0 3.29 18.0 5.01 2.0 12.06 0.2 -12.01 0.50 5.00 These are fantastic results under intensive load changes, with all output holding well. The +12V output fluctuates by only 0.08 when loaded. 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 5 15 10 225W 10 10 15 10 450W 10 10 20 15 675W 15 10 25 15 850W 20 10 35 20 Ripple results are extremely impressive across all output, with the +12V rail peaking at 35 mV @ full load. All fall well within the recommended specifications. Efficiency (%) 100W 90.66 225W 91.45 450W 93.75 675W 91.73 850W 90.68 The power supply, as expected, is extremely efficient, peaking at 93.75% around 50%. It drops down to just below 91 percent at full load, very strong results across the range of output. 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 Digital Sound Level Noise Decibel Meter Style 2 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 Refridgerator 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 29.0 225W 30.4 450W 31.2 675W 33.7 850W 34.3 We have plenty of experience with the Enermax Twister based fans in the past and this configuration is just as impressive. Generally the power supply is inaudible, with the fan only working harder in the last 20% of power output. Even then it would be drowned out by a couple of chassis fans. Temperature (c) Intake Exhaust 100W 35 38 225W 37 42 450W 41 48 675W 43 51 850W 44 53 The large 13.9cm Twister fan maintains a high level of airflow, maintaining good ambient temperatures. At full load the temperature rises to a 9c above ambient intake threshold. Maximum load Efficiency 972W 88.2% Even at 972W, the unit exhibits very strong efficiency levels, measuring 88.2%. Be aware this isn't a realistic long term situation 24/7 but it shows that the power supply has a lot of headroom for quick load situations. We were very impressed when we reviewed the Enermax Platimax 1200W power supply in October last year and we had high hopes that the 850W would be just as impressive. We haven't been disappointed. Enermax have created an improved, updated power supply based around the MaxRevo range of yesteryear. I really do love the finish of these power supplies, they not only look great, but they are resistant to fingerprints and don't mark easily. I tested this by running the tip of a screwdriver lightly down the side of the chassis. It didn't leave a mark. Enermax put their faith in these products, by offering a full 5 year warranty. Internally, the build quality is just as impressive as the outward appearance. The quality of soldering and selection of components is first class. They are using 105c rated Rubycon, Matsushita and Nippon Chemi-con capacitors throughout the Platimax range. On a technical level, there are no concerns to be raised. Load regulation is solid and the design held well when placed under an intensive cross load situation. Efficiency is class leading, peaking at almost 94 percent at around 50 percent load. Importantly Enermax haven't forgotten that noise is a concern and they are using their flagship 14 cm Twister fans to keep the temperatures down while producing low levels of noise. UK availability is limited to a few online stores, such as SCAN. It is a hugely expensive unit priced at £207.53 inc vat, which surely places it out of reach for all but the wealthy enthusiast user. Even then I think those people might spend the extra £65 for the 1200W version. We could score it down a little due to the asking price, but technically it is as good a unit as we have seen. That alone means it will appeal to the wealthy enthusiast user who is unwilling to make any compromises. The rest of us need look elsewhere. Pros: looks beautiful. built to last. quality modular cabling. could deliver almost 1000W in our tests. extremely efficient. Cons: not completely modular. If you are spending more than £200 on a power supply, why not opt for the 1200W version? Kitguru says: Another class leading power supply from Enermax, just be prepared to pay for it.