Here more information on the PSU subject...
Why 80 PLUS® is Irrelevant to You When Buying a PSU
A HardOCP editorial about the 80 Plus® program and how it is changing the computer power supplies you are buying. Is this good, bad, or ugly, and should you care? Did you know that you paid for that 80Plus rating on your shiny new PSU? Certainly PSU efficiency is a great thing, but what about the rating system?
Precious Metal Efficiency is Almost Irrelevant
Of all the things a computer power supply is supposed to do, being efficient is among the least important at this point in time for desktop users and an efficient power supply does not mean that you will necessarily be getting a quality power supply. Now that is certainly not the eco-friendly and politically correct thing to state, but it’s the truth. However, the more important aspects of a power supplies performance aren’t as easy for most people to wrap their minds around and none of these give an easy marketing hook like "efficiency ratings" with pretty colors all the way to platinum. So what does the cost savings look like when you buy an 80 PLUS® certified unit?
There are a few conditions to point out here before we move on. First off, we are greatly simplifying the following examples (including rounding) and using hypothetical power supplies as there are no real examples where the scaling and numbers are this neat. Second, for power used below, it is the AC power pulled at a given DC load instantaneously that is indicated not over time. Third, the cost to run a unit at a given load level and 80 PLUS® certification is calculated based on running the power supply for 24 hours a day at that same exact load and certification level with electricity costing $0.08 kw/h.
Unfortunately, the numbers aren’t great at making the electricity savings of these units into a real factor in deciding on what power supply to buy or upgrade too. Let’s start by looking at generalized cost savings cases exclusive of the cost of the power supply. As stated above, these examples represent drastically simplified situations as your actual load is not going to be static at some percentage determined by 80 PLUS®. You likely aren't running your PC 24 hours a day without a sleep mode enabled. Folding@Home folks however may be, so this may be more realistic for you. (Go [H]orde, Team 33!) So you likely are not going be able to make this direct comparison among all 80 PLUS® certification levels. However, what we can see is a trend and a perspective as to the magnitude of what the different 80 PLUS® certification levels mean to you. Let's look at the 1000 watt power supplies first that hypothetically came in all 80 PLUS® certifications as these units will skew our results in favor of 80 PLUS®'s higher certification levels being relevant more so than the 500 watt examples.
With an 1000 watt 80 PLUS® Platinum power supply, you are looking at saving a grand total of ~$0.24 a day over a base 80 PLUS® power supply if your power supply was running at full load for 24 hours. While that does mean it will save you about ~$88 a year under that scenario to run a 80 PLUS® Platinum power supply instead of a base 80 PLUS® power supply (~$788 compared to ~$876) this advantage dwindles significantly the more you move up the 80 PLUS® scale with 80 PLUS® Bronze, Silver, and Gold units. Additionally, the gap between single levels (Bronze versus Silver for instance) is even smaller.
Now with a 500 watt 80 PLUS® Platinum power supply, you are looking at saving a grand total of ~$0.12 a day over a base 80 PLUS® power supply if your power supply was running at full load 24 hours. Now that does mean it will save you about ~$44 a year under that scenario to run a 80 PLUS® Platinum power supply instead of an 80 PLUS® power supply (~$394 compared to ~$438), however this advantage dwindles significantly again the more you move up the 80 PLUS® scale with 80 PLUS® Bronze, Silver, and Gold units. And again, the gap between single levels (Bronze versus Silver for instance) is even smaller.
To put this into some perspective let’s briefly look at an example of pricing with the closest thing we have to a 500 watt 80 PLUS® vs. 80 PLUS® Platinum scenario. Currently, the 80 PLUS® Platinum Kingwin LZP-550 (an excellent power supply by the way) is available for $159.99 while the 80 PLUS® Silverstone ST-50F 500W is available for $49.99 and Corsair CX500 is available for $39.99. Under the scenarios we constructed above, where your electricity cost savings would be the greatest among 500 watt units, it will take a very long time to make back the price difference when buying the LZP-550.
We are not going to assign solid numbers to the following explanations because so many variables can be introduced. While PSU pricing, usage scenarios, and the cost of electricity are not static, a trend we clearly see is that the higher the level of 80 PLUS® certification on a PSU the more expensive the unit is at its output level. Additionally, while the time to recoup the cost is going to vary, the general trend is that due to the higher pricing of the higher ranked 80 PLUS® units your time to recoup that premium is going to be significantly longer unless you are in a rather narrow niche of people who use their system 24/7 at significant load levels, which the majority of consumers and even enthusiasts are likely not. Lastly, if you are going to replace a functioning power supply it makes almost no sense to do so based on efficiency alone as the time period required to realize a savings under normal usage patterns is going to be even longer. That is assuming the power supply you just bought with that nice 80 PLUS® logo actually is as efficient as the badge "certifies."
80 PLUS® a Marketing Tool?
After discussing how manufacturers cheat 80 PLUS®, the question comes up of why would manufacturers really care enough to play and cheat the 80 PLUS® game so hot and heavy, as we have seen over the last few years? The way we see it is that 80 PLUS® is more about marketing than efficiency.
What [H] Thinks
The 80 PLUS® logo is a big seal of approval that vendors can stick on its product's packaging that slightly informed and even uninformed buyers can form some sort of instant relationship with because the concept of Platinum, Gold, and Bronze "levels" are ingrained in many consumers. Efficiency is also a concept that is much more ingrained in people than electrical principles that actually matter to the hardware being powered by a power supply. Not only that, but 80 PLUS® logos allow power supply manufacturers to ride the eco-friendly wave of late.
Now is 80 PLUS® and energy efficiency bad? No, of course not. One of the problems is the approach that ECOS has adopted leads to ridiculous competition to be the first to achieve something unique inside of this framework to keep this advertising copy fresh even if it is not true or relevant to users. The first 80 PLUS® Gold power supply! The first 80 PLUS® Gold power supply over 1000 watts! The first 80 PLUS® Platinum power supply! The first 80 PLUS® Platinum power supply that will walk the dog! You get it... Beyond the marketing issues, the 80 PLUS® program leads to some corporate behavior that we have to question. There are surely PSU retailers that are looking for ways to exploit 80 PLUS® so it can have a marketing and sales advantage. In the end, companies’ likely play and cheat the 80 PLUS® game because there is significant thinking that the 80 PLUS® badge will make more money than improving its products in other ways, if those even improve efficiency at all. And over the large consumer picture, this is likely the truth.
While, in all honesty, we don’t care that much on a professional level about PSU efficiency as much as other factors when it comes to reviewing or selecting power supplies, manufacturers have decided that for bragging rights it will target users with this approach because it is something the company can use in its marketing. Since most of these PSU companies have found it so important, we hate to find that ECOS seems to have a significant difficulty with policing its certifications. We recently added our own version of 80 PLUS® certification testing to our PSU reviews and will continue to run ECOS' 80 PLUS® certification loads in our reviews. We started doing this because of the intense corporate focus on 80 PLUS® certifications, not because we find these all that useful. If a power supply comes in that misses 80 PLUS® certification numbers by a wide margin we will fail that unit.
The Bottom Line
If you are shopping for a new power supply and you want to buy a more efficient power supply because you think it is an environmentally responsible idea, by all means do it. If you want to buy a more efficient power supply because it also means a higher quality unit, and that has been verified by someone other than ECOS, by all means do it. If you want to buy a more efficient PSU because you think 80 PLUS® means it is a better built PSU that will pay you your price premium back quickly, or that it might be a significantly more efficient PSU based on the ECOS 80 PLUS® certification, please just remember we think 80 PLUS® is irrelevant.