Doing the Math on ECO

On MSI’s website, a number of statements are made by their internal testing.

One picture shows a regular MSI mATX motherboard based on a low cost design drawing 29W. It does not state if this is idle, load or what CPU is used, but based on our testing it could easily be idle numbers with a reasonable CPU and a discrete GPU installed.

Next to the 29W number is an ECO motherboard indicating it uses 22W. Next to this is the same motherboard but with ECO Center software enabled, and 17W being used. MSI’s 40% claim of power reduction comes from the difference between 17W and 29W (~41%). Any company publishing numbers on its own products have a vested interest in making them sound as good as possible, so I took these numbers to run a regular working year analysis on them. Follow the math with me, and see if you agree with my conclusions.

  • Normal motherboard uses 29W
  • ECO motherboard uses 22W, which is 7W fewer
  • ECO with ECO Center software uses 17W, which is 12W fewer

The standard working year is 1920 hours long (8 hours per day, 5 days per week, 48 weeks per year).

This means that each motherboard uses the following amount of energy:

  • Normal motherboard at 0.029 kW for 1920 hours uses 55.68 kWh
  • ECO motherboard at 0.022 kW for 1920 hours uses 42.24 kWh
  • ECO motherboard with Software at 0.017 kW for 1920 hours uses 32.64 kWh

At a price of $0.12 per kWh, this means that:

  • The normal motherboard costs 55.68 * $0.12 = $6.68 per year to run
  • The ECO motherboard costs 42.24 * $0.12 = $5.07 per year, a saving of $1.61
  • The ECO+S motherboard costs 32.64 * $0.12 = $3.92 per year, a saving of $2.76

So by using MSI’s own numbers, an ECO motherboard with ECO center enabled would save $2.76 per year. If we extend that to a 3 year upgrade cycle (based on warranty), that means that the ECO motherboard should only cost an $8.28 maximum difference over the base board. MSI told me that the ECO range would cost 20% more than the standard range, and if that number is accurate, it means that the non-ECO boards should only be $41.40 ($8.28 / 0.2), and the ECO boards should be $49.88 maximum. If MSI were to move on to a five year warranty and this would extend to $13.82 in savings, a $69.12 base price and an $83.94 ECO price.

One quick blast to Newegg shows that the B85M ECO is on sale for $73.

One of the big problems with marketing components like motherboards as ‘eco-friendly’ is that when we are dealing in sub 10W savings, the cost of the extra components can vastly out-weigh the savings unless the product cycle is extended and supported accordingly.

Another interesting point to note is MSI’s quoted effect of the ECO Center software at load. Here MSI quotes 52.1W for an ECO motherboard at load which drops to 50.1W when the ECO Center software is enabled. It comes across a small drop, but that it important when it comes to our numbers.

Our Numbers

While MSI doesn’t state which motherboard they used to get the 29W value, we recently reviewed the MSI Z97I AC and thought that would be a good starting point. Being a mini-ITX motherboard it should have fewer components, but it is in the $140 price bracket and thus has a controller or two.

Normally we do our power readings with the same power supply across all motherboards. This means that while the numbers might be a bit inefficient at the lower part of the spectrum, they are all on the same efficiency line. Using our stupidly overpowered 1200W Gold power supply (for example) and an i7-4770K, the comparison between the Z97I AC and the B85M ECO gives:

Peak Power Consumption w/GTX 770 Equipped
Long Idle 56W 47W
Peak CPU Load (OCCT) 154W 129W

Even if you ignore the power efficiency, we have a 9W difference at idle and a 25W difference at load, which both works out to around 16%.

If we extrapolate 9W out in our mathematics, this equates to $1.84 a year, whereas 25W is $5.76. The more you load up the ECO system, compared to another loaded system, the more savings are to be had is a perfectly valid qualitative conclusion. The ECO certainly scores top marks in our standard motherboard power tests, coming top of our Z97 series by a good margin.

We tested the B85M Eco with four CPUs and two different power supplies with and without a discrete graphics card to get an understanding of how the power savings work. The power supply here is a 500W Platinum unit from Rosewill. All numbers given are peak power readings at the wall for the system as a whole.

Power Consumption w/GTX 770

Power Consumption w/Integrated Graphics

Our testing shows that the ECO mode affects a 1-2W difference in peak loading, but this correlates with MSI’s own numbers when using an ECO board vs. using the ECO board with the software enabled.

It was interesting to see that when the integrated graphics were in play, the i7-4770K downclocked to 3.3 GHz to hit the 85W mark. If we directly compare the POV-Ray results of each CPU in normal and ECO mode, the T/S processors stay within 2% but the 4770K reduces significantly enough to be noticeable:

POV-Ray Results
BIOS Defaults
in ECO Mode
i3-4130T 605 596
i5-4570S 1205 1186
i7-4790S 1336 1333
i7-4770K 1541 1412

MSI claims 100% performance at all times, but our i7-4770K CPU did reduce in frequency to hit the power point. We passed our information on to MSI although we are waiting on an official response. Chances are this behavior will be fixed in a future BIOS update.

MSI B85M ECO Overview, Visual Inspection, Board Features MSI B85M ECO BIOS
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  • Cygni - Wednesday, November 26, 2014 - link

    A Mini-ITX ECO would be right in my wheelhouse.

    I have an HTPC/NAS/Steam Mini-ITX thats on 24/7 and is several years old. It's next replacement cycle would likely last 5+ years, and the lowered power draw (plus lower heat) would be a no brainer over that lifetime. Could also see a market for personal servers and the like in Mini-ITX.

    I would echo the request for undervolting access, even if its rarely worth it. The option would be appreciated to tinker with, if nothing else.
  • PaulJeff - Wednesday, November 26, 2014 - link

    I think the point of these "eco" boards is determined by the economy of scale. For a real world example, you would need to replace dozens if not hundreds of workstations/desktops in an office to realize the true savings potential. If one workstations nets a few dollars a year in savings on power costs, multiply that by the number of workstations that will be replaced, multiply that by the # of years between hardware refresh cycles and that will add up the potential power savings.

    MSI should be selling this "ECO" brand to OEMs like Dell, HP, etc. and then the savings can be distributed on a mass market scale.

    The cost delta between a non-ECO branded board and an ECO board is not worth it for SMB's and home users.
  • - Wednesday, November 26, 2014 - link

    Good price
  • Daiz - Wednesday, November 26, 2014 - link

    The price of electricity does not take into account the true cost of it's generation.

    It might be good to also consider the amount of fuel that is required or carbon output
    for example 1kWh of electricity requires ~0.5kg of coal and produces ?? kg of carbon dioxide.

    so assuming a 5 year upgrade cycle is going to happen no matter what, you are still stopping ~27.5kg of coal from being burned each year or 137.5kg over the life of the mobo. multiple by the number of machines in an office and every little bit helps.
  • Conficio - Wednesday, November 26, 2014 - link

    Should the energy savings and cost savings not also include the cost for air conditioning/cooling? I know that server rooms care about that. So there should be at least some back of the envelope numbers which should increase the amount of savings somewhat.

    I'm just curious.
  • Lerianis - Thursday, November 27, 2014 - link

    One thing I wanted to point out: 300 Watt power supply? Eh eh...... even a bargain basement, non-gaming intended dicrete graphics card needs 400 Watts minimum, unless it is the REALLY cheap ones sold to HP/Dell/Gateway for their office PC's.
    A regular person cannot even order one of those unless they go online and 'lie' to the HP parts person telling them "Yeah, my video card died and I want to replace it myself, can I order one of your replacement discrete graphics cards?"
    400 Watts is a more realistic minimum for a system with a discrete graphics card, though with the new integrated graphics from Intel being able to push HD 1080p and 1920*1080 resolution other content without a stutter while using less than 2% of the CPU's power on an i5..... they might have an argument that no one needs a discrete graphics card who is not an uber-gamer anymore.
  • KAlmquist - Friday, November 28, 2014 - link

    Actually, a 300 watt power supply should be enough to power a single GTX 980. However, Ian was presumably thinking about the standard business PC, which uses integrated graphics these days. As you correctly note in your last paragraph, the primary market for discrete graphics cards is now gamers.
  • jtd871 - Thursday, December 4, 2014 - link


    Thanks for reviewing a non-flagship board. Like others who have commented here, I could see something like this finding a home in a future personal build for productivity, light engineering and moderate gaming. And it's $25 to $50 less than the Z-series boards. Please, more like this in the uATX and mITX form factors!

    Some feedback for MSI (and other board OEMs): ditch the (non-express) PCI already, please? Any business willing to buy enough of these isn't going to stick PCI add-in boards inside (assuming they can still find drivers for use with their modern operating systems). I would suggest eliminating the PCI slot altogether and keeping the x16 slot separated from the other 2 PCIe slots, as a lot of even low-end GPU cards (for business multi-monitor, say) are at least a double-slot width - rendering the 2nd slot unusable in those situations anyway, and make at least 1 of the remaining slots at least physically x8.
  • azazel1024 - Thursday, December 11, 2014 - link

    This seems like a really stupid test of the power efficiency since that is the main focus. A REAL PSU, like a bronze or higher rated PSU in the 350-500w range should have been used. Either a standard B85, or H85/7 or something should have been compared to it. you have a board with an over abundance of features versus one bereft.

    Otherwise it is apples to oranges.

    Also, if MSI's claims are accurate, the ECO frankly sucks. My Sever with a G1610 in it, H67, 8GB (2x4GB) G.Skill Sniper@1.2v, SSD, 2 HDDs plugged in and a pair of Intel Gigabit CT NICs and Antec Earth Watts 380 burned 21w at idle, drives spun down. The ENTIRE system uses less than what MSI claims a typical uATX boards uses at idle. Based on Intel's numbers for some things like the NICs, I have to assume that the board is using at MOST 15w and probably closer to 12w.

    Seems like at most we are talking 2-3w of power savings MAYBE comapred to a VAGUELY similar board.
  • know of fence - Monday, March 2, 2015 - link

    Being an enthusiast site AT always played down power consumption numbers. But just making assumptions and low balling 4 different variables (price, hours, efficiency, years of operation) is both cumbersome and somewhat disingenuous.
    A more elegant way would be to create a realistic range for those variables and combine them into coefficients for min, max and typical scenarios. You could even do typical US, typical EU, UK, India or whatever.
    For me every 1 W saved 24/7 equals 2 EUR/annum, also 66 cent per Watt per year assuming 8 hours a day operation. Not to mention that PCs actually last anywhere from 5 to 10 years, though they are much less frequently used, once they are handed down to relatives.

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