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Topic: Update Large review of Finksy/J4bbrwock server psus compared to ATXpsu-photos up - page 14. (Read 20897 times)

legendary
Activity: 4256
Merit: 8551
'The right to privacy matters'
I saw that link what i will do is get one I will run it with the one s-7 i have and compare it directly to the 2880w i have.

use the pdu meter.   should be an easy direct comparision.

That was the only thing I knew to do as well.  My PDU's have meters but they are whole numbers with no decimal points.  It simply rounds off to the nearest whole number.  I'm going to do a search to find something better if possible.  By the way, I have the APC7911 "Switched" PDU's.  I have not hooked them up yet.  They too are metered.  However, I'm not sure if they have decimal point or not.  Do you?  I have to run another 30A outlet to plug it in.  I do not want to unplug the PDU's I have going at the moment.  They have rigs mining on them.

If you happen to know of something I can get on Amazon and/or eBay that can measure properly without spending too much money, let me know please.


APC7911 has decimal points in the web interface, but not on the PDU its self.

If you want a good/accurate meter, look into the Watts up? meter, the UO version of the .net version is ideal for this kind of testing. Elsewise, I think you'll be spending thousands for something better, like a fluke power meter/analyzer.

My pdu has 1/10 or nearest tenth. It certainly will show close enough to see a large difference between the 2880w and the 2980w.

What we all really need to know is 100 watts a s-7 or 100 watts an Avalon really the difference between the two models.
full member
Activity: 196
Merit: 100
  You guys are too awesome, your detail reviews definitely helps others decide what is best for them (size, efficiency,  noise level, etc).  I just hooked up my next pair of IBM 2K PSU and of course I found out they are the newer Rev so I can't use them with the 4K board voltage controls (Only work with Rev 8 or lower per Finksy).  Going to order a pair of older rev PSU from FINKSY to go with the new 4K board bundle.
  
  For this new pair of IBM 2K PSU, I simply just use the Scotch mounting tape Phillip recommended.
http://www.amazon.com/gp/product/B00004Z498?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s00

 Although they feel weak to the touch, these things are strong as heck when you tape them to something.  They're so strong that I didn't even bother to split out the other pair of PSU to find out the Rev #.  I only use a small piece to attach the FAN together.  Since they're at the bottom of the PSU, I didn't even need to use a mount, just place the PSU (taped together) on top and it's nice and steady on top.  I love this SCOTCH TAPE!  Make this solution clean, sexy and no obstruction to flow.  Guess I wont be needing to buy any fan mounting kit with this Tape.  Op, please quote my message so picture will show.

http://imgur.com/a/MaTjR
legendary
Activity: 1596
Merit: 1000
I saw that link what i will do is get one I will run it with the one s-7 i have and compare it directly to the 2880w i have.

use the pdu meter.   should be an easy direct comparision.

That was the only thing I knew to do as well.  My PDU's have meters but they are whole numbers with no decimal points.  It simply rounds off to the nearest whole number.  I'm going to do a search to find something better if possible.  By the way, I have the APC7911 "Switched" PDU's.  I have not hooked them up yet.  They too are metered.  However, I'm not sure if they have decimal point or not.  Do you?  I have to run another 30A outlet to plug it in.  I do not want to unplug the PDU's I have going at the moment.  They have rigs mining on them.

If you happen to know of something I can get on Amazon and/or eBay that can measure properly without spending too much money, let me know please.


APC7911 has decimal points in the web interface, but not on the PDU its self.

If you want a good/accurate meter, look into the Watts up? meter, the UO version of the .net version is ideal for this kind of testing. Elsewise, I think you'll be spending thousands for something better, like a fluke power meter/analyzer.
legendary
Activity: 4256
Merit: 8551
'The right to privacy matters'
Relax  everyone  I ordered this

 I had a coupon and paid about 140 not 150

http://www.amazon.com/gp/product/B00TMPKE96?psc=1&redirect=true&ref_=od_aui_detailpages00

should be a direct fit and easy to compare to this

http://www.amazon.com/gp/product/B00VMEB944?psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=A25R0MJJKVE76I


this is 76 with shipping.


so say 77 vs 150  or 75 dollars difference .

    I will run with identical testing.   and buyers can tell the watt difference   both should work fine with the breakout board.

The only thing I am sure about today is my titanium 1600 watt evga gets better watts rating then the 2880watt psu.  at freq 600
legendary
Activity: 1596
Merit: 1000
I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

Actually, that's exactly how efficiency is determined. AC input watts VS DC output watts. There is no other way to measure it. Ecova (The company behind the 80+ efficiency program) uses hardware that is worth 5 digits to do the testing, meanwhile I'm using a $200 watt meter and a $300 amp clamp to measure DC output. My results will of course be a little less accurate, but very close nonetheless. I regularly compare my efficiency testing to the 80+ results, and I'm always very close to their results.

Also, server PSU 80+ program is more stringent since they run on 230v. Don't confuse 80+ ATX number with 80+ server numbers:



I was wrong. 87% means the 2880W-ers are actually bronze rated, not silver.

Did you power the fans externally?

4.4.4      Fan Load Considerations

for Single-output Power Supplies
In typical single-output
power supplies (typically used in the
rack mount servers and blade server
applications) the fans are sized not only to remo
ve heat from the power supply but also the heat
from the system. In order to facilitate the system
designer’s use of different
 cooling strategies for
the system, the power consumed by the fan will not be included for efficiency calculations. If the
power supply has an internal fan, then the manuf
acturer will give provis
ion to supply external
power to the fan during the power
supply efficiency testing.
If th
e power supply does not have an
internal fan and if it fails to operate during the
efficiency testing due to thermal cutoff, then an
external fan shall be used to
cool the power supply. The power
 consumed by the external fan
shall not be included in the efficiency calcula
tions. In both cases th
e fan power used during
testing at each load setting
will be recorded for data colle
ction in determining industry
performance of efficiency
with and without fan power.

That is just one small section of relevance in the testing procedure that would skew the numbers by up to 4.3% efficiency.  I also wonder if Bitcoin miners are able to maintain constant load to within +-0.5%. Or if any criteria at all were observed from the 80+ testing procedure in order for you to "Certify" it as bronze.

Again, I would love to see how you tested the units (equipment, conditions, etc). You'll have to forgive me for not simply taking your word for it.  I find it extremely difficult to believe that the Bladecenter PSU's jumped from "Bronze" to Platinum rating overnight when they built the 2980W.


I typed up a very long and detailed reply that for some reason didn't get posted when I hit "post". Pretty infuriating, and I'm not typing it up again so I'll be brief here.

Fans were not powered externally, and I believe that to be disingenuous since no one will use a second power supply to power the main power supply's fan(s) in the real world. Most server PSU fans I've come across are 5-10w. These PSUs definitely use more juice with their fans. Don't think it's enough to bring efficiency down by any meaningful amount, much less 4.3%. Where did you get that figure?

I've already described my testing methods to you. 20-25c ambient, Watts Up? Pro .net AC meter, $300 AC/DC amp clamp to measure DC amperage and multiply it by voltage measured at the load end of wires to account for vdroop. Some simple math then gives us efficiency numbers. IF you don't want to accept my methodology, I'm very open to suggestions to improve my process. It has proven to be very accurate when used with PSUs that have results posted by ecova, even when taking the fan into consideration. Furthermore, a 1500GH/s SP20E has consistently used less power at the wall using an actual platinum PSU vs the 2880W-er by a large enough amount. I do consider that a little unfair since 1 SP20E won't hit 50% load on the 2880w, but on the other hand the other PSU was close to 100% load which lowers it's efficiency.

What you call overnight is actually a 5 to 6 year difference in engineering and manufacturing, a new (better) OEM,  not to mention the adoption of PSU efficiency measures to reduce global power consumption of data centers and consumer IT and a shift to ever more efficient PSUs to meet those goals. The 2880w came before all of that. Don't see why you have such difficulty believing that it's possible. You'll have to forgive me for not taking your word that it's platinum when there is absolutely no proof of that anywhere to be found. I've only seen that it's platinum being parroted on this forum. I hope you'll do your own tests and post the results. Until then, the burden of proof is on you to prove it is platinum and not bronze.

I hope you aren't taking this as a knock on you or j4bber. It is anything but. You guys sell what I consider to be the best server equipment for mining, and I know that you both believed the PSUs to be platinum rated. I know you wouldn't have sold them as platinum power supplies without believing that they were, and no one in their right mind will think that.

Edit: With the exception of S4, what I've seen is a constant load from miners on the power supply. Never seen it move more than 0.1A while mining on S7, for example.
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
I saw that link what i will do is get one I will run it with the one s-7 i have and compare it directly to the 2880w i have.

use the pdu meter.   should be an easy direct comparision.

That was the only thing I knew to do as well.  My PDU's have meters but they are whole numbers with no decimal points.  It simply rounds off to the nearest whole number.  I'm going to do a search to find something better if possible.  By the way, I have the APC7911 "Switched" PDU's.  I have not hooked them up yet.  They too are metered.  However, I'm not sure if they have decimal point or not.  Do you?  I have to run another 30A outlet to plug it in.  I do not want to unplug the PDU's I have going at the moment.  They have rigs mining on them.

If you happen to know of something I can get on Amazon and/or eBay that can measure properly without spending too much money, let me know please.
legendary
Activity: 4256
Merit: 8551
'The right to privacy matters'
I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

David, if you really want to know, a good comparison would be to get one of the 2980W PSU's and measure amperage for a fixed amount of miners over 24 hours, and then do the same with the 2880W with the same miners before you pull the trigger on such a large purchase of PSU's. I'll see if I can track one down myself.

I just paid $150 with free shipping for a 2980 on eBay.  It's supposed to be here no later than January 7th.  I'll get back in touch.  However, I do want some suggestions as to the best possible tool for measuring the amperage.  If it cost a couple of hundred dollars to purchase it, so be it.  The kilowatt meter I bought on Amazon was a piece of crap.  He went out on me after about 30 days.

I saw that link what i will do is get one I will run it with the one s-7 i have and compare it directly to the 2880w i have.

use the pdu meter.   should be an easy direct comparision.

I can run 1 s-7 get pdu meter settings and run 1 s-7 + 1 avalon 6

get pdu reading then   do it with the other .

in theory I should do 5.9/6.0 2880w   then 5.5/5.6 2980w
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
Honestly if that is the case, I will gladly change all my threads to reflect it. But I was always under the impression they were in fact Platinum rated.  I'm hoping J4bberwock will chime in, as he originally had linked to the data sheet (that I can't find now) in his PSU thread before I got involved with them.

I remember that data sheet.  I was trying to find it last night but could not.  I wanted to see what "model" it may had referred to.
legendary
Activity: 1022
Merit: 1003
Honestly if that is the case, I will gladly change all my threads to reflect it. But I was always under the impression they were in fact Platinum rated.  I'm hoping J4bberwock will chime in, as he originally had linked to the data sheet (that I can't find now) in his PSU thread before I got involved with them.
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
That is just one small section of relevance in the testing procedure that would skew the numbers by up to 4.3% efficiency.  I also wonder if Bitcoin miners are able to maintain constant load to within +-0.5%. Or if any criteria at all were observed from the 80+ testing procedure in order for you to "Certify" it as bronze.

Again, I would love to see how you tested the units (equipment, conditions, etc). You'll have to forgive me for not simply taking your word for it.  I find it extremely difficult to believe that the Bladecenter PSU's jumped from "Bronze" to Platinum rating overnight when they built the 2980W.

I honestly believe the 2980's will be at least 6% more efficient at a minimum than the 2880's.  80+ testing procedures did not begin until late 2004.  Which see:  https://en.wikipedia.org/wiki/80_Plus

Who know's how long it was before IBM got around to getting their blade center PSU's rated?  They may not have sought getting them rated until they went with more quality design and components to get as high of a rating as possible for marketing purposes.

"The Climate Savers Computing Initiative efficiency level targets for workstations for 2007 through 2011, correspond to the 80 Plus certification levels. From July 2007 through June 2008, basic 80 Plus level (Energy Star 4.0). For the next year target is 80 Plus Bronze level, the following year 80 Plus Silver, then 80 Plus Gold, and finally Platinum."  https://en.wikipedia.org/wiki/80_Plus

It really wasn't over night either with the creation of the 2980's.  They were made available in late 2010 to 2011.  The 2880's were out for quite a while before the 2980's came on the scene it appears [Maybe 2004 or 2005].  I would have to go along with Prelude on this one at the moment with the 2880's probably being around Bronze and no higher than Silver.  Even if the 2880's are equivalent to a Silver rating, this makes the 2980 a much better buy for one who intends to have a lot of gear mining.  At least after I did the math it appears to be the case.
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

David, if you really want to know, a good comparison would be to get one of the 2980W PSU's and measure amperage for a fixed amount of miners over 24 hours, and then do the same with the 2880W with the same miners before you pull the trigger on such a large purchase of PSU's. I'll see if I can track one down myself.

I just paid $150 with free shipping for a 2980 on eBay.  It's supposed to be here no later than January 7th.  I'll get back in touch.  However, I do want some suggestions as to the best possible tool for measuring the amperage.  If it cost a couple of hundred dollars to purchase it, so be it.  The kilowatt meter I bought on Amazon was a piece of crap.  He went out on me after about 30 days.
legendary
Activity: 1022
Merit: 1003
I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

Actually, that's exactly how efficiency is determined. AC input watts VS DC output watts. There is no other way to measure it. Ecova (The company behind the 80+ efficiency program) uses hardware that is worth 5 digits to do the testing, meanwhile I'm using a $200 watt meter and a $300 amp clamp to measure DC output. My results will of course be a little less accurate, but very close nonetheless. I regularly compare my efficiency testing to the 80+ results, and I'm always very close to their results.

Also, server PSU 80+ program is more stringent since they run on 230v. Don't confuse 80+ ATX number with 80+ server numbers:



I was wrong. 87% means the 2880W-ers are actually bronze rated, not silver.

Did you power the fans externally?

4.4.4      Fan Load Considerations

for Single-output Power Supplies
In typical single-output
power supplies (typically used in the
rack mount servers and blade server
applications) the fans are sized not only to remo
ve heat from the power supply but also the heat
from the system. In order to facilitate the system
designer’s use of different
 cooling strategies for
the system, the power consumed by the fan will not be included for efficiency calculations. If the
power supply has an internal fan, then the manuf
acturer will give provis
ion to supply external
power to the fan during the power
supply efficiency testing.
If th
e power supply does not have an
internal fan and if it fails to operate during the
efficiency testing due to thermal cutoff, then an
external fan shall be used to
cool the power supply. The power
 consumed by the external fan
shall not be included in the efficiency calcula
tions. In both cases th
e fan power used during
testing at each load setting
will be recorded for data colle
ction in determining industry
performance of efficiency
with and without fan power.

That is just one small section of relevance in the testing procedure that would skew the numbers by up to 4.3% efficiency.  I also wonder if Bitcoin miners are able to maintain constant load to within +-0.5%. Or if any criteria at all were observed from the 80+ testing procedure in order for you to "Certify" it as bronze.

Again, I would love to see how you tested the units (equipment, conditions, etc). You'll have to forgive me for not simply taking your word for it.  I find it extremely difficult to believe that the Bladecenter PSU's jumped from "Bronze" to Platinum rating overnight when they built the 2980W.
legendary
Activity: 1596
Merit: 1000
The 105 watts saved for each S7 I'm running adds up.

Seem like a big difference. It should be 2~% efficiency difference between Gold and Platinum. You're talking about an efficiency difference that sound more like Bronze vs Plat than Gold vs Plat.

You may be correct.  I'm not familiar with what percentage puts one in silver, gold, platinum and titanium.  Maybe I should not have used that terminology.  However, I believe if one looks at the actual numbers, they can see the logic behind the power savings which opens up more available power for more revenue.

EDIT:  By the way, Prelude, did say the 2880 is more in "silver" territory than gold or platinum.  I quoted him in my post above.

If the difference is actually 8%, then yes, thats pretty big. 86% efficiency at 8X% load would be silver efficiency and 91% would be platinum.
https://en.wikipedia.org/wiki/80_Plus

It would be a good idea to double check what efficiency those PSU are supposed to make to make sure the watt difference is not a Fluke, because a 8% difference in efficiency is HUGE.

Look at the following link for the numbers on the 2980...  There are no numbers on the 2880 except for those done by members in the forums.  Prelude used a watt meter to check the efficiency at 50% load for the 2880.  He said it was more like 87% at 50% load.  Here is the link for the 2980:  http://www.plugloadsolutions.com/psu_reports/IBM_39Y7414_2980W_SO-188_%20Report.pdf

EDIT:  There is a possibility I'm off by 1%.  Even at 1% off on my figures, the 2980 is still very much worth getting IMHO if one is using MANY PSU's with MANY rigs.

What i'm thinking is the efficiency difference should be about 1%. A 8%, even 7% does not make sense. I'm not sure what's up with all that, maybe the 2880 tested were bad? I think this warrant more testing before throwing an extra 5-10k into 2980's.

I'm curious as to why you think there should only be a 1% difference? The 2880w models were put into production in ~2005. The 2980w models were put into production late 2010. A lot changed in the PSU manufacturing world in those 5 years. 80+ didn't even exist in 2005 I think.. The 7% difference in efficiency is very easy to believe.

Put it this way.... Look how far bitcoin miners have come in the last 5 years in terms of efficiency. Hell, even the last year alone. Now imagine where we'll be in 5 years. Only 1% more efficient? I don't think so.

I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

Actually, that's exactly how efficiency is determined. AC input watts VS DC output watts. There is no other way to measure it. Ecova (The company behind the 80+ efficiency program) uses hardware that is worth 5 digits to do the testing, meanwhile I'm using a $200 watt meter and a $300 amp clamp to measure DC output. My results will of course be a little less accurate, but very close nonetheless. I regularly compare my efficiency testing to the 80+ results, and I'm always very close to their results.

Also, server PSU 80+ program is more stringent since they run on 230v. Don't confuse 80+ ATX number with 80+ server numbers:



I was wrong. 87% means the 2880W-ers are actually bronze rated, not silver.
legendary
Activity: 4256
Merit: 8551
'The right to privacy matters'
I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

David, if you really want to know, a good comparison would be to get one of the 2980W PSU's and measure amperage for a fixed amount of miners over 24 hours, and then do the same with the 2880W with the same miners before you pull the trigger on such a large purchase of PSU's. I'll see if I can track one down myself.


I think if you could use the same 2 s-7's at the same setting on the 2880w for 24 hours

then do the same test with the 2980w  for 24 hours.


My issues in comparing the 2880watt  to the 1600 t2 evga   were that the 2880w provided 12.20 volts and the evga provided 12.04 volts  thus  when you set at freq 600  the string design of the

s-7 simply spends the extra power with no hash gain.

so at freq 600 the evga was a lot better

but at freq 637 the evga was a dog and the 2880 watter was good.

Basically the test was not fair since  dc volts are different.
legendary
Activity: 1022
Merit: 1003
I would also love to know the methods used to determine the 2880W PSU efficiency.  The 80+ program is more involved than just measuring input amps and output amps from what I gather.

David, if you really want to know, a good comparison would be to get one of the 2980W PSU's and measure amperage for a fixed amount of miners over 24 hours, and then do the same with the 2880W with the same miners before you pull the trigger on such a large purchase of PSU's. I'll see if I can track one down myself.
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
What i'm thinking is the efficiency difference should be about 1%. A 8%, even 7% does not make sense. I'm not sure what's up with all that, maybe the 2880 tested were bad? I think this warrant more testing before throwing an extra 5-10k into 2980's.

I can agree with your assessment.  I'm searching the web now for specifications.
legendary
Activity: 1302
Merit: 1068
The 105 watts saved for each S7 I'm running adds up.

Seem like a big difference. It should be 2~% efficiency difference between Gold and Platinum. You're talking about an efficiency difference that sound more like Bronze vs Plat than Gold vs Plat.

You may be correct.  I'm not familiar with what percentage puts one in silver, gold, platinum and titanium.  Maybe I should not have used that terminology.  However, I believe if one looks at the actual numbers, they can see the logic behind the power savings which opens up more available power for more revenue.

EDIT:  By the way, Prelude, did say the 2880 is more in "silver" territory than gold or platinum.  I quoted him in my post above.

If the difference is actually 8%, then yes, thats pretty big. 86% efficiency at 8X% load would be silver efficiency and 91% would be platinum.
https://en.wikipedia.org/wiki/80_Plus

It would be a good idea to double check what efficiency those PSU are supposed to make to make sure the watt difference is not a Fluke, because a 8% difference in efficiency is HUGE.

Look at the following link for the numbers on the 2980...  There are no numbers on the 2880 except for those done by members in the forums.  Prelude used a watt meter to check the efficiency at 50% load for the 2880.  He said it was more like 87% at 50% load.  Here is the link for the 2980:  http://www.plugloadsolutions.com/psu_reports/IBM_39Y7414_2980W_SO-188_%20Report.pdf

EDIT:  There is a possibility I'm off by 1%.  Even at 1% off on my figures, the 2980 is still very much worth getting IMHO if one is using MANY PSU's with MANY rigs.

What i'm thinking is the efficiency difference should be about 1%. A 8%, even 7% does not make sense. I'm not sure what's up with all that, maybe the 2880 tested were bad? I think this warrant more testing before throwing an extra 5-10k into 2980's.
legendary
Activity: 1302
Merit: 1318
Technical Analyst/Trader
The 105 watts saved for each S7 I'm running adds up.

Seem like a big difference. It should be 2~% efficiency difference between Gold and Platinum. You're talking about an efficiency difference that sound more like Bronze vs Plat than Gold vs Plat.

You may be correct.  I'm not familiar with what percentage puts one in silver, gold, platinum and titanium.  Maybe I should not have used that terminology.  However, I believe if one looks at the actual numbers, they can see the logic behind the power savings which opens up more available power for more revenue.

EDIT:  By the way, Prelude, did say the 2880 is more in "silver" territory than gold or platinum.  I quoted him in my post above.

If the difference is actually 8%, then yes, thats pretty big. 86% efficiency at 8X% load would be silver efficiency and 91% would be platinum.
https://en.wikipedia.org/wiki/80_Plus

It would be a good idea to double check what efficiency those PSU are supposed to make to make sure the watt difference is not a Fluke, because a 8% difference in efficiency is HUGE.

Look at the following link for the numbers on the 2980...  There are no numbers on the 2880 except for those done by members in the forums.  Prelude used a watt meter to check the efficiency at 50% load for the 2880.  He said it was more like 87% at 50% load.  Here is the link for the 2980:  http://www.plugloadsolutions.com/psu_reports/IBM_39Y7414_2980W_SO-188_%20Report.pdf

EDIT:  There is a possibility I'm off by 1%.  Even at 1% off on my figures, the 2980 is still very much worth getting IMHO if one is using MANY PSU's with MANY rigs.
legendary
Activity: 1302
Merit: 1068
The 105 watts saved for each S7 I'm running adds up.

Seem like a big difference. It should be 2~% efficiency difference between Gold and Platinum. You're talking about an efficiency difference that sound more like Bronze vs Plat than Gold vs Plat.

You may be correct.  I'm not familiar with what percentage puts one in silver, gold, platinum and titanium.  Maybe I should not have used that terminology.  However, I believe if one looks at the actual numbers, they can see the logic behind the power savings which opens up more available power for more revenue.

EDIT:  By the way, Prelude, did say the 2880 is more in "silver" territory than gold or platinum.  I quoted him in my post above.

If the difference is actually 8%, then yes, thats pretty big. 86% efficiency at 8X% load would be silver efficiency and 91% would be platinum.
https://en.wikipedia.org/wiki/80_Plus

It would be a good idea to double check what efficiency those PSU are supposed to make to make sure the watt difference is not a Fluke, because a 8% difference in efficiency is HUGE.
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