Topic: ANTMINER S7 is available at bitmaintech.com with 4.86TH/s, 0.25J/GH - page 280. (Read 527809 times)

I asked if I could mention this on the forum.
Have been buying from him since s3 days.
Just bought 3 more B2

I saw it but I don't believe it unless Yoshi confirms.  This buy US with a extra warranty seems to be something only you have done, which is odd.

I cant imagine going to support and ask to buy gear.  But I could be wrong Yoshi is a nice guy. 

What I'm about to say is only speculation:

I'm pretty sure the fans will draw more current as the temperature rises.  When the fans turn at higher RPM's it results in more current draw.

As for higher hash rates and lower HW errors; this one blows my mind as well.  I know in the wire-line telephone industry, the amount of resistance we have in the cable per foot changes with temperature.  The cooler the temperature [Due to contraction - getting smaller in diameter] the wire would have more resistance per foot.  The warmer the temperature [Due to expansion - getting larger in diameter] the wire would have less resistance per foot.

I'm sure it probably gets more deep than just the resistance changing with temperature.  That's why I said someone with more experience in electronics might be able to elaborate on the subject.

The only thing I can "speculate" on is with the warmer temperatures and expansion of material and components in the blades possibly resulting in less resistance to impede transmission.  However, there is a breaking point at how hot is too hot where the material and components can break down.  I'm sure others with more experience would be able to elaborate on this with a more informative explanation than mine.  I'm only speculating.  That's it...

I know manufacturers of ASIC's have implemented circuits that are programed to throttle down an ASIC once it gets to a certain temperature and even shut the ASIC down once it gets to an even higher temperature to avoid potential meltdown and/or fire.

Edit: Once the rigs get above a certain temperature and potentially that creates even more expansion of materials that could be enough to affect the capacitance in the blades.  For example, the two copper wires with a poly-etholine coating on them in the wire-line telephone industry are twisted together.  These two wires are in essence a capacitor, which is at least 2 metal plates separated by an insulator(s).  Three things that affect the value of a capacitor is the size of the metal plates, distance between the plates and the material between the plates.  As the capacitance increases [Due to expansion - larger metal plates] higher frequencies are affected by this increase in capacitance.  I will not elaborate on how and why [Taking up too much space in the forum] but it does affect them.

So, the only thing I can speculate on is the resistance in the materials used in the blades decreases with temperature rise because of expansion.  This reduced resistance increases the hash rate and reduces the hardware errors.  However, if the temperature continues to rise to a point of creating considerable expansion of those materials to change the capacitance, it can affect the impedance in the blades so much that it reduces the hash rate and increases the HWE's.  Again, this was only speculation.

I know hybrids in carriers in the telephone industry have to be a certain impedance: 640 ohms for non-loaded pairs and 900 ohms for loaded pairs.  If we ever have a customer's line not loaded properly, it can change the impedance on the line [Making it not balanced with the hybrid in the carrier] and can potentially create echo-return-loss or reflection in the signal in certain situations.  That could be what is occurring when the temperature gets too radically hot above the high 60's or 70's; creating echo return loss or reflection of the transmission between components [because of a change in capacitance], which could increase errors and reduce hash rate.

That was my two cents.  It was given to encourage discussion and thought on the subject.  I promise, I will not curse out anyone this time if anyone was to chime in.  

So you need more heat AND less freq? Not just lower frequency?

Wait a minute -- Usually its the other way around ... cool off IC's/CPUs and they function better...

The antminer chips NEED heat??? Odd.

I know with the S2's, the hotter they ran, the more current they sucked. This summer the landlord at the office I was renting shut off the AC and the miners were running with 90+ degree F. intake air which made the chips cook at 75 C. to 80 C. I didn't notice any better hashrate with them.

This is excellent information
Must be what they did to mine.
This will save a bunch of experimentation

Did you get the post of email  from Yoshi?

EtherApe(for root) is nice for linux users to find IP's and to see what's talking and to where........

I recommend ipscan24 for finding devices on a network.

Amen to that. My ignore button just took another hit 

Ahhh.......that's better.

I like the ipreporter.exe for S7 that allows you to hit the button to the left of the ethernet cable and have the ip address pop up.

It might be time for you to heed this advice, wouldn't you think?

As for your B2/B3 confusion - if the message is real then it might be a typo. B1 and B3 have identical specs so there wouldn't be a reason to ship only 11 out of 12 B1 and then some B3, instead of completing the B1. It would make more sense if they had underperforming miners not suitable for B1 and shipped them as B2.

In any case, if you get the miners and they run at 600 MHz - good for you.

From Yoshi:

You can mention the purchase option via usa!

844-248-6246 or Bitmain.zendesk.com

Price is a bit more compare to the chinese purchase price but for multiple unit purchase custimers, this usa purchase may help avoids the headache of clearing the custims via ups and be billed the fee later.

Warranry claim pricess be a hassle free model vs 4-6 weeks process via the factory.


I'm sorry for the wait!

WTF!

Does everyone here live in Missouri??? You know, the Show Me State.

 

 

Try not to worry - I'm sure things will work out, it can be a little worrying with your first order from Bitmain, especially with the high prices they are charging, but I'm sure your miners will come eventually - it's just a case of when. Be patient. I know it's hard when we read about the horror stories about delivery - & posts like wolfen's certainly don't help. We can't make him prove himself, but if he can't, well, then we'll all know the truth. I heard they did have an official shill once, but he was terrible at it - so they sacked him 

bitmaintech does not need shills.

I rather you be wrong.

But maybe you are not wrong.

So does anyone besides wolfen have a 'real' tracking number for batch 2 or 3?

IN no way am I angry or complaining about this rollout of gear.  my first ones  came fast and both work fine. I just like to track the  gear from China to New Jersey while it is actually happening.

Can you give more details?  I know they have support there.  But I honestly have not heard of a way to purchase through them, let alone a 100 dollar us warranty.

Who are you purchasing from at the office?   Can you show emails edited?  I just have a hard time believing it.

I was totally out of line.  I could not see his face nor hear his tone or lack there of.  I just flat out misunderstood what he was implying and got worked up over it and lost my shiznit.  If we were on the phone or talking face to face, the entire thing could have been avoided.  I apologized in a PM and deleted my post shortly after the PM.  I learned a valuable lesson from all of this.  I really feel bad about the whole thing.  The important thing is I have learned from it and will try not to make the same mistake again.



I agree with this 100%

No shill here sir. No troll either. This is the first and only forum I have used.
I pretty much figured things out myself.
I have been waiting 7 weeks for my miners, it is exciting to see people get theirs.
I get and have gotten all my antminers from the Denver Bitmain office over the years. (s3,s3+,s5,s7)
I'm just a programmer. Older than dirt.
Denver offers $100 USA warranty so you don't have to send sick ones back to China.
Small price for quick turnaround.
Bitmain Denver 844-248-6246.
This is just how I purchase. Wanted to share. It's nice to help folks out
I was on the phone with a gentleman for an hour helping him get the s5 I sold him up and running.

Yeah, they're especially great when you disagree with his method or outcome then he loses his shit on you.  He does quickly delete the posts and apologize, so at least his heart is in the right place. 

But I digress, take the information here as opinion, not fact.  Ask someone qualified who's familiar with your infrastructure and building codes.   Anyone worth their salt will give their opinion but won't guarantee anything until they see it first hand.