XFX XTR 550 Fully Modular Power Supply Review

Introduction One of the latest XFX power supplies is on our test bench today, bringing 550W of power as well as 80 Plus Gold efficiency to your system, making it a solid contender for most mid-to-high end gaming PC's. Many people think they need 1000W plus from their PSU, but that simply isn't the case, with most high-end single GPU systems rarely drawing more than 400-500W from the wall. Being a Seasonic manufactured unit, I'm expecting great things from the XFX XTR Series 550W PSU. "Designed for serious gamers and DIY professionals, the XFX XTR Series 550W Full Modular 80 Plus Gold power supply delivers the clean and stable power required for demanding gaming rigs and workstations. A single strong 12V rail flexibly routes the maximum available power to the parts, enabling you to maximize power usage and making setup easy. It's also been awarded the 80Plus Gold certification for its high power efficiency, and is also designed for NVIDIA SLI and AMD Crossfire multi-GPU systems, making it a perfect solution for hardcore gamers. Its modular design reduces cable clutter. And the large fan delivers silent cooling, so your computer and PSU can operate at peak performance." Equipped with a powerful single +12V rail configuration, modular cables, CrossFire/SLI compatibility, Haswell support and much more, this is certainly a capable unit for a wide range of systems. Of course, you'll also find it comes equipped with all the latest safety features, as well as high-quality Japanese capacitors, which should allow for clean and stable power delivery. As with many Seasonic manufactured units, this PSU also comes equipped with a Hybrid Fan, allowing you to switch between always on cooling and a semi-passive mode, perfect for those who desire maximum performance or silent operation. EasyRail Plus Technology allowing plenty of wattage headroom to handle your devices Hybrid Fan Control allowing the power supply to operate silenty until it reaches 20% load or 25C Ultra Quiet Fan Design Ultra Voltage Regulation Design Haswell Ready AMD Radeon CrossFire Ready NVIDIA GeForce SLI Ready Multiple PCI-E 6-Pin and 6+2Pin connectors True Wattage guarantee 80 Plus Gold certifying 90% power efficiency Extreme heat tested capacitors The packaging is very nicely designed, with some stylish images on the box as well as a rundown of the major features, such as Haswell Ready, Japanese Caps, SLI/CrossFire and 80 Plus Gold efficiency. Another important feature on the back, the True Wattage Guarantee, always a reassuring thing to see and something we'll certainly hope to see in our test results. In the box, you'll find a durable power cable, some mounting screws and a user manual, nothing too fancy, but it's everything you're going to need. A Closer Look - Exterior Typical of other XFX units, we've got that funky fan grille that is obviously practical in the sense that it lets the air in, but it's also a style point that's going to look pretty cool inside your system; who said PSUs have to look boring! On the base, we've got a bit of branding, as well as the specification chart. There's an impressive 45A no the +12V rail, more than enough juice to power a couple of graphics cards, or a single very power hungry card. The side of the XTR is nicely designed too, with a painted on and purposely faded logo, surrounded by an embossed design that adds a little bit of flair to what could otherwise be a blank panel. Lots of ventilation around the back for heat dissipation, as well as more branding, should you forget this is an XFX XTR from any particular angle. There's obviously the AC line-in, as well as a handy master power switch. All the fun stuff is around this side, with that special hybrid/normal fan switch, a split 24-pin connector, four 6-pin peripheral connectors, as well as 4 x 8-pin connectors, one of which you'll need for the motherboard 4+4 connector. Cabling All of the cables are of a very high quality, with all black cables and black connectors, so they should be easy to blend in with your current system build. All of the cables are flat too, which will make cable routing/management a whole lot easier, with the exception of the 24-pin motherboard cable, which comes treated with a flick all-black braiding. A Closer Look - Interior This is only a 550W unit, so there's not really a lot of hardware on the interior. This does mean there's a good amount of free space between the major components, and this will help greatly with heat dissipation and allow for good airflow from the fan. Despite the limited hardware, there are still four small heat sinks, which should again help remove even more heat from the unit; they'll no doubt help greatly with the passive/hybrid fan modes. The main bulk capacitor is a Hitachi brand component and is rated for 330 uF, 420v and 105c. The secondary capacitors are all high-quality components, with a mixture of Rubycon and Nippon Chemic-Con components that will provide the smaller voltages for this unit. There are quite a few wires here, but they're bundled well and kept out of the way of the main interior of the unit, so they shouldn't affect airflow or cooling. The line filtering stage goes straight into a small vertical PCB, shielding it from the other components nicely, which should help reduce crosstalk. From there is moves into the bridge rectifier via the main PCB and past that first small heat sink. Here you'll find a smaller PCB, which houses the various controllers and PFC hardware. The soldering on the PCB is as tidy as you could hope for, with any sensitive or closer hardware protected by protective film dividers and/or glue spots. A good quality HA13525H12F-Z fan, the same model seen in other XFR series and Seasonic G-Series units, a perfect choice thanks to its many fan blades and capabilities to run at low RPM. Test Procedure At eTeknix we take the power supply testing procedure very seriously and have invested a lot of resources into acquiring the appropriate testing equipment. For all power supply reviews we test the power supplies with dedicated power supply testing equipment. This means we are able to get the most accurate results from our testing as opposed to using software benchmarks (such as OCCT) or multi-meter readouts which are broadly inaccurate. Our test machinery is as follows: Sunmoon SM-5500ATE Active Load Tester (1200W rated) Stingray DS1M12 USB Oscilloscope Voltcraft DT-10L laser tachometer The eTeknix test procedure involves: Testing each power supply at 20/40/60/80/100% load (with balanced load across all rails) and measuring PFC (power factor correction), efficiency (actual power divided by power "pulled at the wall") and voltage regulation (deviance from expected voltages of 3.3/5/12 on the main rails). Measuring ripple with an oscilloscope at 20/40/60/80/100% load. Measuring fan speed after a stabilisation period of five minutes at each load scenario using the Voltcraft DT-10L laser tachometer and a reflective strip on the fan. Testing each power supply's OPP (Over Power Protection) mechanism and seeing how many watts each power supply can deliver before shutting down Other things to consider are that We recognise that a single yellow 12 volt cable can provide only 6 Amps before overheating (which corrupts voltage regulation and efficiency) and so we used an adequate number of cables for each power supply to ensure there is not efficiency loss from poor cables selection Our Sunmoon SM-5500ATE power supply tester is not capable of testing more than 300W on each of the 12 volt rails so where a power supply provides more than 300W on a 12 volt rail that power is distributed over multiple 12 volt rails on the load tester. For example a power supply with one 12 volt rail supplying 750 watts would be spread equally over three 12 volt rails on the load tester, a power supply with two 450W 12v rails would be spread over four 12v rails on the load tester, two 225W 12v rails for each of the 12v rails on the unit. We use the same time scale and horizontal millivolt scale on our oscilloscope for all ripple tests, that is a 20ms T/DIV (horizontal) and a 0.02 V/DIV (vertical) meaning the scale is from -80mV to +80mV, ATX spec dictates that the 12v rail must fall within 150mv of ripple and the 3.3/5 within 50mv so that scale allows us to include both 150 and 50mV peaks. (Some older PSU reviews use different scales which were later ditched as the visual representation they give is inadequate, in these reviews written measurements are provided only). Deviance is the terminology used to represent the way voltages diverge from the expected values Efficiency, PFC and Voltage Regulation Voltage Regulation To test voltage regulation we load the power supply to five different load scenarios that give an equal spread of load across every single rail. So that means 20% on all rails, 40% on all rails and so on. We then calculate the average deviance of each rail from its expected voltage. The voltage regulation is very good here, with very little deviance across various load scenarios. Some rails are around 1% out from spec, but this is well within safe tolerances and the results are reasonably consistent from 20% through to 100% loads. Power Efficiency Power efficiency is measured by calculating actual supplied wattage divided by the wattage drawn at the wall/plug, multiplied by 100 to give a percentage. We then compare that to the particular 80 Plus certification the company claims to see if it meets that. You can see the 80 Plus certifications below, we always test 230v power supplies. The 80 Plus Gold rating delivered right on its promise, delivering exactly what we would have expected across all loads. Power Factor Correction Power Factor Correction is the ratio of the real power flowing to the load, to the apparent power in the circuit. The aim of PFC is to make the load circuitry that is power factor corrected appear purely resistive (apparent power equal to real power). In this case, the voltage and current are in phase and the reactive power consumption is zero. The closer the number to one the better as this allows the most efficient delivery of electrical power (Source - Wikipedia). Being a Seasonic unit, I was expecting this result to be good and sure enough, it hasn't disappointed one bit, this as good as any PSU I've ever tested has done, a very good result. Ripple Noise and Ripple can easily be measured by an oscilloscope. These show how much voltage fluctuation there is on a particular rail. We tested the rail stability of the 3.3 volt, 5 volt and 12 volt rails using an identical time and millivolt scale for all graphs. millivolt ripple is measured by the peak to peak size of the voltage curve. The latest ATX 12 volt version 2.3 specifications state that ripple from peak to peak must be no higher than 50 millivolts for the 3.3 volt and 5 volt rails, while the 12 volt rail is allowed up to 120 millivolts peak to peak to stay within specifications. Millivolt figures are stated to the closest increment of 5 given their variability. Load (%) 3.3V Ripple 5V Ripple 12V Ripple 20 4 4 9.2 40 5 4.4 13.2 60 6.4 5.8 18.4 80 8.6 8.6 20.2 100 11.6 18.8 27 Extremely tight ripple suppression here, very good results across the board, so much so that I could actually double all of the numbers and they would still be fairly good results. 3.3 volt @ 100% 5 volt @ 100% 12 volt @ 100% Over Power Protection and Max Wattage Power supplies often quote as having various protection mechanisms such and the most important of these is Over Power Protection. In our testing we crank up the power draw until the power supply either shuts down (meaning the OPP mechanism is present and working) or blows up (meaning it is either not present or not working). We then note the maximum power consumption before the power supply shut down (or blew up). Not the biggest result ever, but certainly enough headroom to deal with any power spikes. This being a well-made unit, I wouldn't be surprised to see it run past 600W all day long, ever day, without any issue; that's the quality you get with a unit like this. Fan Speed When testing in a power supply laboratory it is difficult to take fan noise readings as the noise from the Sunmoon test equipment and air conditioning corrupts everything. The next best thing in our circumstances was reading off the fan speed with a tachometer to get an idea for the noise. The ambient temperature during testing held constant at 22 degrees, with 1 degree of variation. Each power supply had a consistent time period of 5 minutes to stabilise between each load scenario. In my experience, the following general relationships apply between noise levels and fan speeds, though it can vary greatly between the type of fan used. Below 800 RPM - Inaudible/Silent 800 to 1000 RPM - Barely audible 1000 - 1200 RPM - Audible but still quiet 1200 - 1400 RPM - Moderately noisy 1400 - 1800 RPM - Noisy 1800 RPM or higher - Intolerable The fan speed really didn't want to do much of anything until it got past 80% load, however, at maximum the fan really did spin up quite a lot, but honestly wasn't as noisy as we were expecting, easily on par with the 1200-1400 section of our scoring system. The same results were to be found in Hybrid fan mode, albeit the 60% and below loads resulted in much lower or completely off fans speeds. Final Thoughts Pricing The XFR is certainly a competitive unit, with many retailers in the UK listing them for around £65, this is a very good price for a unit of this quality and the confidence you get from it having a 5-year warranty only helps sweeten the deal even further. Readers in the US can pick up the unit for $89.99. Conclusion This isn't the greatest PSU in the world, it is after all only a mid-to-high end unit, targeted at the bulk of PC gaming consumers. Typically, I would recommend this unit for someone running a single powerful GPU, but there's no doubt a few crossfire or SLI configurations that aren't too power hungry that would be just as happy with it, especially with many newer cards offering very efficient power designs. Build quality is premium throughout, despite the affordable price tag. This is what I would have expected from a unit made by Seasonic, as they didn't come one of the best in the industry by turning out cheap units. Everything from the flat all black and fully modular cables, to the detail of the soldering on the internal PCBs, it's all super neat and tidy and I doubt many people will need to exercise that 5-year warranty. The hybrid fan mode is a welcome addition, as it does slow the fan right down and even stop it in very low load scenarios, giving you perfectly silent performance when you're doing simple day to day tasks such as browsing the web. When you're gaming the PSU will obviously spin the fan up and keep it cool and while it did get a little noisy at 100% load, it's unlikely you'll be putting that amount of strain on the unit often, if you are, you need a higher wattage PSU. 80 Plus Gold efficiency is a good standard to aim for, it gives you a good amount of savings in terms of electricity costs, without having to make too much investment on the cost of the PSU, as you would with Platinum or Titanium rated units. The efficiency is certainly a by-product of the high-quality components used and overall, this would make a great PSU for many system builders or those looking to upgrade an older unit. Pros Good efficiency Fully modular design Flat all-black cables Excellent PFC Good voltage regulation Low ripple 5-year warranty Exceptional build quality Cons High fan speed at 100% load Hybrid fan mode doesn't make a huge impact on fan speeds "The XFX XTR 550W Power Supply offers excellent build quality, matched with clean and stable power that makes it an ideal choice for many system builders. The competitive price and 5-year warranty " Thank you XFX for providing this review sample.