what is the most efficient PSU ?

[arik100]

which PSU is the most efficient ?
i know about 80% of corsair and enermax , but there is more???

 

[Dangman]

Just look on the 80Plus website. Should be able to find PSUs that are are more efficient than Corsair and certain Enermax PSUs.

 

[JonGerow]

Buty also keep in mind that if you're going from 82% to 85%, for example, you're only saving about $10 a year if you run your PC 24/7 (not including stand by and hibernation modes.)

 

[PhatalOne]

Before the semi-on-topic rant... The Enermax MODU82 and PRO82 series are nice power supplies that can almost meet Bronze certification from 80PLUS.

If you don't feel like reading, the concise version is at the bottom.

Another important point to remember about the 80 plus certification is that it applies to only system load of 20%, 50%, and 100% of rated power. For example: An 80+ certified 300w power supply, must provide 80% efficiency at system loads of 60, 150, & 300 watts. Compare this to an 80+ 1000w power supply, it only has to be 80% efficient when providing 200, 500, & 1000w! Below 200w the 1000w supply has no efficiency requirements and most power supplies experience a significant drop in efficiency below that threshold. While the areas between 20% and 50% and 50% and 100% are unregulated, most power supplies will maintain at least 80% efficiency in those ranges.

Overall, 80PLUS is a great tool. However, like any tool, if not used properly it won't achieve the desired results. If efficiency is your goal, I would highly recommend estimating your system's idle power draw and full load requirements and choose an 80PLUS that meets both of these requirements. So don't pick the biggest power supply you can find, pick the one that will best fit your system's intended usage profile.

Concise version:
1.) 80+ certification means that your power supply is 80+ efficient at 20%, 50%, and 100% of the PSU's rated power.
2.) Under the 20% rating, all power supplies will drop below 80% efficiency at some point, some much more so than others. Between 20-100% most power supplies can maintain 80% or better efficiency.
3.) Determine decent estimates for your idle and max power usage profiles.
4.) To maximize your system efficiency, look for an 80PLUS power supply that meets both your idle and max power profiles.

 

[exe]

There was another issue I read up on that I didn't think about when I purchased my Enermax Modu82+, and that is the power draw when off. Supposedly, the Modu/Pro 82 does not do too well in that department. More likely than not, the average computer user has their computer turned off the majority of the time, so the efficiency of the power supply is negated by a higher draw during off state. For best results, turn off your power strip that your computer is connected to.

 

[JonGerow]

2.) Under 20% all power supplies will dip under 80% efficiency.

That is not always true.

Although many PSU's that are 80 Plus certified may drop below 80% below 20% load, not ALL power supplies drop below 80% below 20% load.

 

[PhatalOne]

Although many PSU's that are 80 Plus certified may drop below 80% below 20% load, not ALL power supplies drop below 80% below 20% load.

Jon, I know "all" is a sweeping generalization. First, I want to make clear to others, that it only applies to 80PLUS power supplies (the entire topic of my first post). Given the currently available power supplies that are 80PLUS certified, I've yet to see a single power supply that maintains 80% efficiency at all points below 20% of rated wattage. If there is a power supply on the consumer market that is 80% efficient from 0-20% of rated power and still meets 80PLUS certification, I would really like to know. I am looking for the most efficient power supply I can find for my systems, and thus far have not found a power supply that meets 80PLUS and is 80% efficient from 0-20% of load.

 

[PhatalOne]

There was another issue I read up on that I didn't think about when I purchased my Enermax Modu82+, and that is the power draw when off.

That's a great point, I hadn't really thought about that since my main interest in high efficiency PSU's has been for systems that run 24/7.

 

[JonGerow]

Jon, I know "all" is a sweeping generalization. First, I want to make clear to others, that it only applies to 80PLUS power supplies (the entire topic of my first post). Given the currently available power supplies that are 80PLUS certified, I've yet to see a single power supply that maintains 80% efficiency at all points below 20% of rated wattage.

Ok. You didn't say "all point". The way it sounded was that as soon as the PSU drops below 20% load it's immediately NOT 80% efficient. There are certainly a lot of PSU's out there that are very efficient at 20% and up, but are very INefficient at lower loads, especially stand by (which is where most PSU's are most of the time.)

If there is a power supply on the consumer market that is 80% efficient from 0-20% of rated power and still meets 80PLUS certification, I would really like to know. I am looking for the most efficient power supply I can find for my systems, and thus far have not found a power supply that meets 80PLUS and is 80% efficient from 0-20% of load.

Not to be a shill, but....

http://hardwarelogic.com/news/136/ARTICLE/3271/2/2008-04-11.html

Unfortunately, even 146W is 18%, but 85.5% efficiency is pretty good none the less. This is accomplished by modulating the frequency of the AC to DC conversion down so the PSU acts more like a 400W PSU than an 800W PSU. Also, the +5VSB is a separate unit within the housing, so when the PC is "off, it's not using an inefficient primary circuit engineered to put out 800W of power. It's using a smaller sub-power supply engineered to only put out up to 20W.

It would be nice to see a reviewer do a "round up" that compared stand by power consumption. Because everyone likes to talk about how their PSU is so efficient at "typical loads" but I know my wife and I and folks at work don't ever really turn our PC's off. So "typical" in my mind is idle or standby. NOT 50% work load.

 

[PhatalOne]

Reading my first post again, I can understand where you might have thought I meant immediately, I've edited that point for clarity. It's funny/amazing how the advance of technology in computers over the years has constantly made every single part more important. I must admit, if someone told me I would care about power supply efficiency, 12v rails, etc 5 years ago, I would of laughed.

85.5% is excellent at 18%. Even though 146w is quite a bit of power at 18%, I think it highlights just how important picking the right power supply can be these days. After all, you can easily build systems that would idle at 146watts by throwing in a few video cards in SLI. After reading the review, I would really be interested to know how low the ES-800 could go and still maintain 80% efficiency since no lower figures were given.

 

[kadozer]

You asked. Here it is Zippy

 

[JonGerow]

You asked. Here it is Zippy

Zippy makes some fantastic product, but the OP's question was "what is the most efficient". Zippy's not listed at 80 Plus (although Zippy claims that their medical PSU's are listed) and I haven't seen any reviews showing that they have outstanding efficiency. Do you have links?

 

[Colin Dean]

The Tuniq Ensemble 1200W boasts minimum 82% efficiency with average 86% efficiency. It's a lot of power, but it's apparently really efficient.

 

[exe]

hey guys, also if you're in North America or in a country with 120vAC, if you read all the reviews, AC voltage of 220 have a few percentage of higher efficiency curve vs 120v AC. So I was thinking, if you want to go to the extreme, couldn't you plug in to the 220v outlet like that used in your washer/dryer?