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.