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Topic: ANTMINER S7 is available at bitmaintech.com with 4.86TH/s, 0.25J/GH - page 130. (Read 527798 times)

E
full member
Activity: 234
Merit: 100
Batch 8 / DPS-2000BB efficiency measurements teaser shot:




BTW at default settings this wiring setup drops about 7W between the PSU output capacitors and the hashboard input pins
 
Setup is 5 x 5mm^2 x 25cm wire pairs, each feeding two PCIe plugs of unknown provenance through 3 x .8mm^2 x 2cm pairs.
PSU mating part is AMP6450552-1

Observed voltage drop at 100A draw is 0.068V  (12.174V - 12.106V) implying end-to-end round-trip resistance of ~.7mΩ, including PSU & PCIe contact resistance.
E
full member
Activity: 234
Merit: 100
Yes definitely Luck.  My Batch 8 using the same 220V IBM 2KW won't change in hash rate by moving to 775 or 800M.  Have to increase the voltage to see some gain like what Phillip did.

There is no point in changing the voltage on a Batch 6, 8 or 9. They have a Buck Converter built onto the Hash board that controls the voltage sent to the chips. Good news is that at some point I am sure a mod will be available that will enable the Core Voltage to be adjusted.

I'm interested in changing Vin to the buck converter to find the maximum efficiency, not in changing Vout to overclock the chips; the LM27402 in this configuration should be able to hold Vout of 10.1 with Vin in lower 11s and it's conceivable to see +/- 1% efficiency over the Vin range 11.6 to 13.3. Numbers / photos soon.

The closest Vin is from Vout, the better your efficiency.
I haven't checked if there is lm27402 design tool/spreadsheet available, but I used the one for LM27403 in a design, and I can confirm that changing Vin can give some efficiency improvement.
Unfortunately, we are already quite close, so I don't believe you can improve efficiency by 1%.

I'll be starting the DC power measurements tomorrow and probably posting before the new year - but I suspect you are right and that the improvement from 12.2V to 11.6V will be less than 0.5%.

Actually at this Iout it's possible the most efficient input voltage is somewhat above the minimum; in any case the LM27402 in this circuit can't do lower than Vin ≈ 1.05Vout...
legendary
Activity: 1260
Merit: 1006
Mine for a Bit
Here are the current stats for my wolfpack
These are running in a datacenter.
Temps seem a bit cool.
218 will be here tomorrow.
These are all batch ones.




Gotta Love the Wolf Pack!  Lookin Good!
hero member
Activity: 840
Merit: 1000
Yes definitely Luck.  My Batch 8 using the same 220V IBM 2KW won't change in hash rate by moving to 775 or 800M.  Have to increase the voltage to see some gain like what Phillip did.

There is no point in changing the voltage on a Batch 6, 8 or 9. They have a Buck Converter built onto the Hash board that controls the voltage sent to the chips. Good news is that at some point I am sure a mod will be available that will enable the Core Voltage to be adjusted.

I'm interested in changing Vin to the buck converter to find the maximum efficiency, not in changing Vout to overclock the chips; the LM27402 in this configuration should be able to hold Vout of 10.1 with Vin in lower 11s and it's conceivable to see +/- 1% efficiency over the Vin range 11.6 to 13.3. Numbers / photos soon.

The closest Vin is from Vout, the better your efficiency.
I haven't checked if there is lm27402 design tool/spreadsheet available, but I used the one for LM27403 in a design, and I can confirm that changing Vin can give some efficiency improvement.
Unfortunately, we are already quite close, so I don't believe you can improve efficiency by 1%.

Edit:
The design calculator is available, I ran some numbers assuming 200kHz switching frequency (most likely value with 2 mosfest in parallel), and 11.6 to 13.0v won't really change anything in efficiency.
And since the switching frequency is already at 200kHz, there is no gain to expect by changing it neither.

Edit2: I checked the frequency adjust resistor, and it's indeed set for 204kHz, so no gain to expect by lowering the frequency, it's already at its lowest value.

The only option left to get a better efficiency is by changing Vout
E
full member
Activity: 234
Merit: 100
Yes definitely Luck.  My Batch 8 using the same 220V IBM 2KW won't change in hash rate by moving to 775 or 800M.  Have to increase the voltage to see some gain like what Phillip did.

There is no point in changing the voltage on a Batch 6, 8 or 9. They have a Buck Converter built onto the Hash board that controls the voltage sent to the chips. Good news is that at some point I am sure a mod will be available that will enable the Core Voltage to be adjusted.

I'm interested in changing Vin to the buck converter to find the maximum efficiency, not in changing Vout to overclock the chips; the LM27402 in this configuration should be able to hold Vout of 10.1 with Vin in lower 11s and it's conceivable to see +/- 1% efficiency over the Vin range 11.6 to 13.3. Numbers / photos soon.
hero member
Activity: 588
Merit: 500
LOL! Want me to send you cryptographic proof of a multi-meter reading or something? Just tryin to be helpful.

Get used to it.... I have just about got to the point that I can post up some information without having to back it up with photographs...  Smiley


Rich
member
Activity: 117
Merit: 10
As a quick FYI, in my limited experience the bitmain PSUs are a good 5% more efficient than the 2000w DPS's.

you must be pretty limited then Tongue

no facts, #'s, or anything to claim your "limited" experience.


LOL! Want me to send you cryptographic proof of a multi-meter reading or something? Just tryin to be helpful.
legendary
Activity: 1500
Merit: 1002
Mine Mine Mine
As a quick FYI, in my limited experience the bitmain PSUs are a good 5% more efficient than the 2000w DPS's.

you must be pretty limited then Tongue

no facts, #'s, or anything to claim your "limited" experience.


back to s7 topic, i have a board sent to bmt too, now waiting. everything looks good no loose heatsinks, so far nothing burnt (that i can see visually see) but bmt says: *in every reply*

"Engineers will double check the issue after they get them and confirm whether it's due to the boards themselves or improper use. if the boards are burnt due to improper use ,you may need to cover the repair cost."

me no likey the BOLD  Angry
hero member
Activity: 895
Merit: 504
Hi Everyone.


So normally I wouldn't rant about support topics, But I have 2 major issues I have been trying to resolve over the last few days with no joy.

Now I will start by saying bitmain have normally been really good and solve issues quickly, but I don't seem to be getting anything  resolved at the moment so any advice would be much appreciated.

The first issue I have is that my latest S7 that is currently sat in customs has an invoice attached saying the value of the 1x S7 is $30,000 and they want £5000 for the VAT.

Now as far as im aware the S7 I ordered should be valued at $1650 but it seems that there has been some sort of admin error on bitmains side, I did receive an email from bitmain stating that we needed to pay our VAT or the machine would be sent back to them, I advised them of the issue and they sent over the correct invoice to me, but Fedex have request an explanation from bitmain and a copy of the invoice directly from them, so far fedex has not received a response and neither have I.

The next issue im having is with one of our current S7 machine from batch 5 has an issue,  I checked all my machines the other day and noticed a very strong electrical burning smell and noticed 2x hashing boards had gone down.

I assume they have died but cannot check as there is a warranty sticker over the machine that I do not want to touch without the permission from bitmain, So far I have emailed info@ sent a message through zendesk and also messaged zendesk when live support was available and have so far received no response.

I feel a little ignored and for the first time in 2 years im annoyed at the way Bitmain is dealing with my issues, we have easily spent well over $30,000 with them, not much compared to some bigger miners but enough to think they would as least help.

Like I said I have been more than happy with Bitmain products and there support in the past, but feel very ignored at the moment, and any advice would be greatly appreciated.



The thing that really bothers me about the S7 is the new Bitmain warranty policy stating that if anything burns on the board, there is no warranty.
It's likely that they wanted to avoid replacing boards overclocked/modded, but it also prevent honest users like you, who either got bad luck, or falling heatsinks (engineering failure) for example, to get warranty.
I hope they will reconsider it, at least for the defects caused by falling heatsinks.

If I'm not mistaken, on a batch 5, there shouldn't be any buck converters, unlike the 135 chips units.
So the most likely dead components are an asic, a capacitor, or one of the small LDOs creating the communication voltages (usually 1.8v).

You can start by shaking the unit to check if you hear a something like a heatsink that went loose.
If that's the case, you can remove one fan without losing the warranty to confirm.

You can try to negociate with them if it's a heatsink issue because there is no way they can take you as responsible for it.

Other burnt parts can be caused either by a user overclocking the unit to death, or simply by one bad component in a batch, so it's a bit harder.

If they are totally out of warranty, I'd be interested to grab one board shipped to France for experimenting.


Even though Bitmain's policy states no warranty for burned boards, Bitmain replaced 2 of my burned boards from B1 for free including shipping both ways. I didn't open the miner on my own, I emailed them that two of the boards don't hash. They asked me to open the miner and check the boards. I found loose heatsinks and burn marks. Turnaround time was less than a week after I mailed the boards.
member
Activity: 117
Merit: 10
As a quick FYI, in my limited experience the bitmain PSUs are a good 5% more efficient than the 2000w DPS's.
member
Activity: 117
Merit: 10
It's fascinating watching you guys discus all of this. I wish I could contribute, but it's a good country mile above my head. Here's hoping a way to adjust voltage is found, since B8 definitely doesn't respond to increased 12V from the PSU as earlier batches do.

What is not known, at the moment, is exactly how this addition is being used by Bitmain. At one extreme it is just a Factory set fixed voltage used to make the best of the different batches of BM1385 at a given default frequency. At the other end of the scale the Microcontroller has connection to the System Controller and it's just waiting for a release of firmware to add adjustable voltage. Off at an angle from the extremes  Smiley we have  Cyper_BLC theory that it is a second layer of closed loop, safety based voltage control.


Interesting! I'd toss my vote towards safety control--they have a financial disincentive to allow you to undervolt and underclock. Looking forward to having a look at the circuit they are using. If anybody looks can you post pics? Maybe that's already been posted pages back?
hero member
Activity: 840
Merit: 1000
Hi Everyone.


So normally I wouldn't rant about support topics, But I have 2 major issues I have been trying to resolve over the last few days with no joy.

Now I will start by saying bitmain have normally been really good and solve issues quickly, but I don't seem to be getting anything  resolved at the moment so any advice would be much appreciated.

The first issue I have is that my latest S7 that is currently sat in customs has an invoice attached saying the value of the 1x S7 is $30,000 and they want £5000 for the VAT.

Now as far as im aware the S7 I ordered should be valued at $1650 but it seems that there has been some sort of admin error on bitmains side, I did receive an email from bitmain stating that we needed to pay our VAT or the machine would be sent back to them, I advised them of the issue and they sent over the correct invoice to me, but Fedex have request an explanation from bitmain and a copy of the invoice directly from them, so far fedex has not received a response and neither have I.

The next issue im having is with one of our current S7 machine from batch 5 has an issue,  I checked all my machines the other day and noticed a very strong electrical burning smell and noticed 2x hashing boards had gone down.

I assume they have died but cannot check as there is a warranty sticker over the machine that I do not want to touch without the permission from bitmain, So far I have emailed info@ sent a message through zendesk and also messaged zendesk when live support was available and have so far received no response.

I feel a little ignored and for the first time in 2 years im annoyed at the way Bitmain is dealing with my issues, we have easily spent well over $30,000 with them, not much compared to some bigger miners but enough to think they would as least help.

Like I said I have been more than happy with Bitmain products and there support in the past, but feel very ignored at the moment, and any advice would be greatly appreciated.



The thing that really bothers me about the S7 is the new Bitmain warranty policy stating that if anything burns on the board, there is no warranty.
It's likely that they wanted to avoid replacing boards overclocked/modded, but it also prevent honest users like you, who either got bad luck, or falling heatsinks (engineering failure) for example, to get warranty.
I hope they will reconsider it, at least for the defects caused by falling heatsinks.

If I'm not mistaken, on a batch 5, there shouldn't be any buck converters, unlike the 135 chips units.
So the most likely dead components are an asic, a capacitor, or one of the small LDOs creating the communication voltages (usually 1.8v).

You can start by shaking the unit to check if you hear a something like a heatsink that went loose.
If that's the case, you can remove one fan without losing the warranty to confirm.

You can try to negociate with them if it's a heatsink issue because there is no way they can take you as responsible for it.

Other burnt parts can be caused either by a user overclocking the unit to death, or simply by one bad component in a batch, so it's a bit harder.

If they are totally out of warranty, I'd be interested to grab one board shipped to France for experimenting.
hero member
Activity: 895
Merit: 504
The label I've seen on the Batch 8 boards states BM1385+ Anyone can confirm anything regarding older batches?
So maybe hand picked chips, or a minor revision on the second batch from the foundry.
3 month after first release seems correct to have chips manufactured with a minor update on them.

Yes I wondered about the 1385+ label. You might be right and it is a chip rev? Something similar has been seen before on a 54 Chip board.

http://www.slotforum.com/forums/uploads/1450698776/gallery_2150_2322_63936.jpg

I do not know which batch this was, but this label also has BIN2 which I thought might be a selection?


Rich

I have received a few replacement boards for a B1 with BIN2 label on the board but not 1385+.
legendary
Activity: 1456
Merit: 1000
Yes definitely Luck.  My Batch 8 using the same 220V IBM 2KW won't change in hash rate by moving to 775 or 800M.  Have to increase the voltage to see some gain like what Phillip did.

There is no point in changing the voltage on a Batch 6, 8 or 9. They have a Buck Converter built onto the Hash board that controls the voltage sent to the chips. Good news is that at some point I am sure a mod will be available that will enable the Core Voltage to be adjusted.


Rich

It's kinda good and bad news.  It's good that there is a option someday there.   But bad that we really don't know how long till someone mod's it.   And with warranty I'm not sure how many will try during it or if after.  It will  be pretty obvious a mod on that if you needed warranty work.

I will be more positive on it's possibilities after I see it being modded.  Which I guess might not be that long depending on who is working on it.
newbie
Activity: 54
Merit: 0
Hi Everyone.


So normally I wouldn't rant about support topics, But I have 2 major issues I have been trying to resolve over the last few days with no joy.

Now I will start by saying bitmain have normally been really good and solve issues quickly, but I don't seem to be getting anything  resolved at the moment so any advice would be much appreciated.

The first issue I have is that my latest S7 that is currently sat in customs has an invoice attached saying the value of the 1x S7 is $30,000 and they want £5000 for the VAT.

Now as far as im aware the S7 I ordered should be valued at $1650 but it seems that there has been some sort of admin error on bitmains side, I did receive an email from bitmain stating that we needed to pay our VAT or the machine would be sent back to them, I advised them of the issue and they sent over the correct invoice to me, but Fedex have request an explanation from bitmain and a copy of the invoice directly from them, so far fedex has not received a response and neither have I.

The next issue im having is with one of our current S7 machine from batch 5 has an issue,  I checked all my machines the other day and noticed a very strong electrical burning smell and noticed 2x hashing boards had gone down.

I assume they have died but cannot check as there is a warranty sticker over the machine that I do not want to touch without the permission from bitmain, So far I have emailed info@ sent a message through zendesk and also messaged zendesk when live support was available and have so far received no response.

I feel a little ignored and for the first time in 2 years im annoyed at the way Bitmain is dealing with my issues, we have easily spent well over $30,000 with them, not much compared to some bigger miners but enough to think they would as least help.

Like I said I have been more than happy with Bitmain products and there support in the past, but feel very ignored at the moment, and any advice would be greatly appreciated.

hero member
Activity: 588
Merit: 500
The label I've seen on the Batch 8 boards states BM1385+ Anyone can confirm anything regarding older batches?
So maybe hand picked chips, or a minor revision on the second batch from the foundry.
3 month after first release seems correct to have chips manufactured with a minor update on them.

Yes I wondered about the 1385+ label. You might be right and it is a chip rev? Something similar has been seen before on a 54 Chip board.



I do not know which batch this was, but this label also has BIN2 which I thought might be a selection?


Rich
hero member
Activity: 770
Merit: 523
You sure you don't want to send me a virus or something ? Tongue
I have already downloaded it from the forum
Great, glad you got it. If you need someone to vouch for my character just ask dmwardjr sir.
hero member
Activity: 840
Merit: 1000
The earlier batches probably have more, undervolted chips. While the later batches have less, overvolted chips. So i'm guessing the earlier batches with the most chips would be able to get the most out of overvolting.

Assuming nothing else fry when you try it.


There is probably not much in it, except of course for the greater number of chips favouring the 162 chip systems.
The 162 chip miner with 12v across the 18 Chip string gives a core voltage of 0.667V
The 162 chip miner with 12.2v across the 18 Chip string gives a core voltage of 0.678V
The 135 chip miner with 10.12v (measured by J4bberwock) across the 15 Chip string gives a core voltage of 0.675V

A bigger factor may be if they have been selecting BM1385 chips, which of course we will never know?

Rich

The label I've seen on the Batch 8 boards states BM1385+ Anyone can confirm anything regarding older batches?
So maybe hand picked chips, or a minor revision on the second batch from the foundry.
3 month after first release seems correct to have chips manufactured with a minor update on them.
legendary
Activity: 1120
Merit: 1001
You sure you don't want to send me a virus or something ? Tongue
I have already downloaded it from the forum
hero member
Activity: 770
Merit: 523
Where do I get M Miner Monitor from ?

Thanks
PM your email and I'll send you a copy.
Or you can get it from citronick
I cannot find it on the web any more.
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