Seasonic FOCUS PX-850 850W Full-Modular PSU

I’ve become a big fan of the seasonic power supplies. This is my 4th build in about 8 years using seasonic products and all are still running. This one is especially easy to configure and install. The compact size of this model makes it ideal for the Micro ATX and Mini ITX cases while delivering power enough for even the hogiest of video cards. This model is a tiny 150mm x 140mm x 86mm. This small size provided plenty of room for the connectors and cables, behind the supply in my micro ATX case. If you’ve ever worked with these small form factor cases, you know space is a premium and this supply frees up at least a centimeter over others in this class. The other great thing about this card is the lack of noise. It is one of the quietest I have used. I had it installed with cables run in just a few minutes. The only nit might be that the cable mesh covering does not quite reach the ends of the cable on the power supply end, (few would do that). however the cable that is exposed is very nicely colored (black with gray highlight) so it looks great to me. Highly recommend, especially for small cases.

Fonctionne super bien , Bonne qualiter une des meilleur du marcher , tres silencieux

Typically, people think about almost everything else in a PC first like a graphics card, CPU etc., then the power supply last. Though in fact power supplies are arguably the most important part to any build. Think about it this way, they convert high AC power from your typical home to DC power that every electronic in your systems can use. Essentially it is the heart of your system, but instead it delivers power instead. So, if your heart isn’t running at optimal efficiency then you wont be either. Again, the analogy applies to your PC, though in this case, and analogy, you can buy a better/more efficient heart.

That’s where the Seasonic Focus Plus Series comes in! Now I specifically purchased the 850 Platinum (SSR-850PX) and truly love this thing. Not only does it have awesome features like modularity, OPP/OVP/UVP/SCP/OCP/OTP, high 70A on the 12+ rail (makes 840W basically the whole power supply), but its small efficient and reliable! Seasonic power supplies are one of the most reliable in the power supply business. Plus spending a bit up front on a higher efficiency power supply will over time save you money, and the Focus+ line have a 10-year warranty to ensure those savings.

Before I get into the math behind power efficiency calculations. All of these calculations were done using the general knowledge from Seasonic’s website and USA kilowatt-hour power averages and a little understating of power calculations that anyone could do on their own.

So, let’s get right into it (with the help of spreadsheets)! Using all the standards from 80 Plus (80%) up to Titanium (90%) we can get the cost in electricity over time. So, the more efficient the power supply is running the less power is lost in terms of heat. So, to get relatively linear accurate results for one day we multiply a kilowatt-hour of use ($0.12 is US average) times hours in use per day, then multiply those by the ratio of actual wattage pulled and max wattage of the PSU. So for an efficiency of 89 running at max load for 24 hours it would look like 0.12*24*(901/850)=$3.04 of electricity used for a full day in use. As it can be seen the higher the efficiency the lower the cost per day. Graphing this trend over 10 years shows that buying a more efficient power supply can save money for a small initial investment.

Also, that is expecting the power supply will last that long to achieve the savings. Even after 3 years the trend is clear the more efficient power supplies will save money. So, buying a power supply with a longer warranty will ensure those savings. Additionally, buying a cheaper power supply with lower efficient rating will most likely fail sooner and you’ll have to buy another one anyways.

Though it’s important to note that initial power supply cost, kilowatt-hour, and specific efficiency tolerances may vary per model, USA location, and wattage. With all that considered the overall electricity calculation methodology can apply for all configurations of PSU’s.

The TL;DR version:
Invest a bit and buy a higher efficient power supply. It will be a high cost initially, but after about 2-3 years your guaranteed to be saving money overall in electricity. Plus, you’ll have a much more reliably power supply with a longer warranty to power your expensive equipment. Also, you’ll be helping the environment with less electricity used!

This review was a non-biased factual review written by an average consumer with access to general product information. All calculations could be redone to verify the results obtained in the associated images. Hope this review helps someone understand power efficiency a little better!

Seasonic, pues que decir? excelente nivel de PSU, súper silenciosa, totalmente modular los cables, el empaque, todo se siente premium (llegó en tiempo y forma; perfectamente empacada)

This is a great power supply. You know when you take it out of the box, the weight feels solid. Then you take it out of the included cloth pouch and you really feel the quality craftsmanship on the brushed exterior . The modular design is nice and the included cables are top notch. A bit stiff at first, but you can make them do what you need for optimal cable management. It pumps out the power i need for my new rig.
I bought a Seasonic back in 2011. That rig is still going strong with the same power supply. Its what sold me to stick with them again 8 years later. Love this company.