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Author Topic: ANTMINER S7 is available at bitmaintech.com with 4.86TH/s, 0.25J/GH  (Read 527635 times)
yslyung
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December 23, 2015, 08:32:10 PM
 #5721

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
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December 23, 2015, 08:44:51 PM
 #5722

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.

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December 23, 2015, 08:49:36 PM
 #5723

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

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December 23, 2015, 10:02:15 PM
 #5724

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.
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December 23, 2015, 10:23:28 PM
Last edit: December 23, 2015, 10:41:23 PM by J4bberwock
 #5725

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

Custom Server PSU breakout boards, 1200w, 1300w, 2000w, 2880w https://bitcointalk.org/index.php?topic=738527.0
Btc: 1J4bberWs6f6XVQ53gn3BNc8qHAicmm7wu
Ltc: LNDmMBtzD3cduwjfxANm2wDrxt9jXRk5ZP
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December 23, 2015, 10:28:40 PM
 #5726

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!

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December 23, 2015, 10:35:41 PM
 #5727

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...
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December 23, 2015, 11:05:18 PM
Last edit: December 23, 2015, 11:49:39 PM by E
 #5728

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.
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December 24, 2015, 12:16:44 AM
 #5729

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.



I don't really have any advice, because I'm in a rather similar situation.
I've had quick response with Bitmain - always within 24 hours - until my recent request to return 2 x S7 Hashboards.
At first they responded quickly and gave me return mailing information, but failed to respond to my inquiries about an S5 board.  I even brought up batch 1 compensation.
Needless to say i haven't heard anything back.  They have received the 2 x S7 hashboards about 1.5 weeks ago now.  I emailed again asking about the status a couple days ago and still have no reply.
I did proceed to order 10 batch 8 units and they did ship and arrive within 5 days of the order however.  That was nice, but nothing from support.  Size of customer doesn't seem to matter as I've spent significantly more than you have.  Also received an overvalued customs bill.  20 units were valued at $128,000 instead of $35K on one of my orders.  I have a "grievance" filed with Fedex customs.  May take 6 months to resolve.  LOL.  I don't have to pay the import fee until it resolves.  It looks to me that someone entered the Bitmain Reference number in the unit value field instead of the actual value.
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December 24, 2015, 01:32:45 AM
 #5730

partially OT: 15 mil mined, just 6 mil to go (EVER!)
https://blockchain.info/charts/total-bitcoins

make you miners count...
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December 24, 2015, 01:46:28 AM
 #5731

partially OT: 15 mil mined, just 6 mil to go (EVER!)
https://blockchain.info/charts/total-bitcoins

make you miners count...

Yet I don't own a full bitcoin, every coin went to Bitmaintech  Sad but plan to save all the earnings from now on.

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December 24, 2015, 02:03:40 AM
 #5732

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.

This is a good example of customer service by Bitmain. I hope to see more experiences like this shared on the forums. While I do not like to see bad experiences we need to hear about those as well, but if you are having a reasonable response such as this, please make sure you share it! It shows improvements by bitmain, and we need to know.

Please tell us the step by step. Who you contacted and how, and who took care of your issues, sent the RMA, etc. It may help others immensely.
Thank you for sharing.

Transaction fees go to the pools and the pools decide to pay them to the miners. Anything else, including off-chain solutions are stealing and not the way Bitcoin was intended to function.
Make the block size set by the pool. Pool = miners and they get the choice.
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December 24, 2015, 02:32:49 AM
 #5733

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.

This is a good example of customer service by Bitmain. I hope to see more experiences like this shared on the forums. While I do not like to see bad experiences we need to hear about those as well, but if you are having a reasonable response such as this, please make sure you share it! It shows improvements by bitmain, and we need to know.

Please tell us the step by step. Who you contacted and how, and who took care of your issues, sent the RMA, etc. It may help others immensely.
Thank you for sharing.

I am impressed the way Bitmain handled my warranty claim. I sent an email to info@bitmaintech describing the issues I was having, only 1 out of 3 boards worked out of the box. Wrote order number and problem on the subject line. Also added type of power supply I was using, in this case a Bitmain 1600 watter, sent a picture of input voltage with a  voltmeter just in case.  Got a reply from Sherry Liu, she asked if I opened the miner yet, if not open and inspect. I found loose heatsinks and burn marks on the boards after opening up the miner. I sent pictures to Sherry. She approved the RMA and sent me prepaid shipping labels. Note because of time difference it is not fair to expect a reply within an hour or two, wait at least 24 hours or longer depending when you sent your email. After shipping out the boards, replacement boards were at my doorstep in 7 days. I ordered more than 10 S7s from Bitmain and this is the only S7 that gave me trouble, they are all hashing at their advertised speed or faster. Also it is good to be polite, I am sure Bitmain didn't mail a defective miner, things get rough during shipping.

For quality risers, splitters or 133 CFM fans, please visit my eBay listings,
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December 24, 2015, 02:53:25 AM
 #5734


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.

I vaguely remember reading that somebody either has seen or was hoping to see that one of RFB1 (more likely), RFB2 is settable via a micro? Anybody have a picture of the in vivo circuit?


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December 24, 2015, 07:47:19 AM
 #5735

I vaguely remember reading that somebody either has seen or was hoping to see that one of RFB1 (more likely), RFB2 is settable via a micro? Anybody have a picture of the in vivo circuit?



It is discussed earlier in this thread Rfb2 to ground is adjustable as described here.


I have not fully sussed it but am making progress with the better picture. R15, 20K is not the Reference resistor it's part of the compensation network to pin 3 of the Buck with C73 & C75. The reference resistor (fb1) is R9, 82K taking the voltage from the Converter output.The resistor to ground (fb2) is R10, 6K8.

However this is where it get's interesting and I have not fully worked it out. In parallel with R10 to Ground is a series combination of R17, 12K and U2.

Which of course begs the question as to exactly what U2 (AG30 on one board AG6K on the other) My guess is that it's a single channel Digital pot controlled over I2C by the PIC, but more work needed to confirm this.


There is a  MCP4017-503E Digital Pot IC in series a 12K in parallel with the 6K8 Rfb2.

If you scan back through the thread there is further information and discussion. Another snip here.


I have done some maths on the Digital Pot, which has 32 127 positions, in combination with the 6K8 to ground & series 12K. So assuming it is a 50K Pot we get.

        Supply V   Core V
Min       8.63        0.58
Mid       9.17        0.61
Max     11.87        0.79


Which would be a very sensible range of core voltages, so may be correct?




Rich

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December 24, 2015, 08:23:35 AM
 #5736

I vaguely remember reading that somebody either has seen or was hoping to see that one of RFB1 (more likely), RFB2 is settable via a micro? Anybody have a picture of the in vivo circuit?



It is discussed earlier in this thread Rfb2 to ground is adjustable as described here.


I have not fully sussed it but am making progress with the better picture. R15, 20K is not the Reference resistor it's part of the compensation network to pin 3 of the Buck with C73 & C75. The reference resistor (fb1) is R9, 82K taking the voltage from the Converter output.The resistor to ground (fb2) is R10, 6K8.

However this is where it get's interesting and I have not fully worked it out. In parallel with R10 to Ground is a series combination of R17, 12K and U2.

Which of course begs the question as to exactly what U2 (AG30 on one board AG6K on the other) My guess is that it's a single channel Digital pot controlled over I2C by the PIC, but more work needed to confirm this.


There is a  MCP4017-503E Digital Pot IC in series a 12K in parallel with the 6K8 Rfb2.

If you scan back through the thread there is further information and discussion. Another snip here.


I have done some maths on the Digital Pot, which has 32 127 positions, in combination with the 6K8 to ground & series 12K. So assuming it is a 50K Pot we get.

        Supply V   Core V
Min       8.63        0.58
Mid       9.17        0.61
Max     11.87        0.79


Which would be a very sensible range of core voltages, so may be correct?




Rich

[High-Fives Rich.] Thanks! Off to do my readin. I guess I might be pulling apart a unit after all one of these days.

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December 24, 2015, 08:40:53 AM
 #5737

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.

This is a good example of customer service by Bitmain. I hope to see more experiences like this shared on the forums. While I do not like to see bad experiences we need to hear about those as well, but if you are having a reasonable response such as this, please make sure you share it! It shows improvements by bitmain, and we need to know.

Please tell us the step by step. Who you contacted and how, and who took care of your issues, sent the RMA, etc. It may help others immensely.
Thank you for sharing.

I am impressed the way Bitmain handled my warranty claim. I sent an email to info@bitmaintech describing the issues I was having, only 1 out of 3 boards worked out of the box. Wrote order number and problem on the subject line. Also added type of power supply I was using, in this case a Bitmain 1600 watter, sent a picture of input voltage with a  voltmeter just in case.  Got a reply from Sherry Liu, she asked if I opened the miner yet, if not open and inspect. I found loose heatsinks and burn marks on the boards after opening up the miner. I sent pictures to Sherry. She approved the RMA and sent me prepaid shipping labels. Note because of time difference it is not fair to expect a reply within an hour or two, wait at least 24 hours or longer depending when you sent your email. After shipping out the boards, replacement boards were at my doorstep in 7 days. I ordered more than 10 S7s from Bitmain and this is the only S7 that gave me trouble, they are all hashing at their advertised speed or faster. Also it is good to be polite, I am sure Bitmain didn't mail a defective miner, things get rough during shipping.

my case is also handled by sherry, yes i agree be patient with her, but she does reply within 24 hours or so & she even replies after office hours. once she replied me past 9pm china time.

now it's my turn to wait. package is clearing customs. let's see what does bmt engineers say. miners not oc'ed at all.

i hope it gets fixed or replaced asap.
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December 24, 2015, 08:55:50 AM
Last edit: December 24, 2015, 09:16:03 AM by E
 #5738

Batch 8 on DPS-2000BB @ 743Mhz:



This is exclusive of the fans. System efficiency will depend on your cooling situation.

This works out to just over 0.27W/Gh/s - and the DPS-2000BB can do better with higher (edit for clarity:)inputline voltage

Vac       207.56
Vsupply 12.032
Vchain   10.281

I'll screenshot the miner interface once it's been running for a few hours but this is essentially 4.95TH; 0.016%HW; 60C board temps
yslyung
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December 24, 2015, 09:02:55 AM
 #5739

Batch 8 on DPS-2000BB @ 743Mhz:



This is exclusive of the fans. System efficiency will depend on your cooling situation.

This works out to just over 0.27W/Gh/s - and the DPS-2000BB can do better with higher input voltage

Vac       207.56
Vsupply 12.032
Vchain   10.281

I'll screenshot the miner interface once it's been running for a few hours but this is essentially 4.95TH; 0.016%HW; 60C board temps

pump up the volt on the dps, it should workout better & can go either higher or lowers the HW errors for sure.

ah i just saw it's a B8 hmmm but good to see some diff #'s.

i saw on phillipmas post & j4b's post they went higher with higher volts but of course it's the earlier batches.

i'm still happy at stock clocks but after the 90 days, he he he he !
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December 24, 2015, 09:13:33 AM
Last edit: December 24, 2015, 09:31:09 AM by E
 #5740

Batch 8 on DPS-2000BB @ 743Mhz:



This is exclusive of the fans. System efficiency will depend on your cooling situation.

This works out to just over 0.27W/Gh/s - and the DPS-2000BB can do better with higher input voltage

Vac       207.56
Vsupply 12.032
Vchain   10.281

I'll screenshot the miner interface once it's been running for a few hours but this is essentially 4.95TH; 0.016%HW; 60C board temps

pump up the volt on the dps, it should workout better & can go either higher or lowers the HW errors for sure.

ah i just saw it's a B8 hmmm but good to see some diff #'s.

Yeah exactly, but I'm comfortable w/ that HW %. I don't think it reflects a condition that's likely to shorten the useful life of the unit and it's low enough not to effect utility measurably.
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