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So, i`m always interested in knowing whats being used in various products of mine, that includes my miners. So first thing i did was to strip down the B3 to see what they`re using.

I have never seen the kind of controller that is used in these B3`s however it states that its a T9 controller so i guess they are used on those too. The controller have a lot of external memory connected to its ZYNQ processor unit, not sure why 2GB of memory would be needed on such application.

https://preview.ibb.co/dQ0jVd/DSC_0025.jpg (https://ibb.co/jp4BAd)

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Each B3 hashboard consists of 4 BM1680 "Neural Processors" from Bitmain. There seems to be no external memory attached to the hashing boards, even though the BM1680 supports DDR4-2666 Memory.
BM1680 Wiki: https://en.wikichip.org/wiki/bitmain/sophon/bm1680

https://preview.ibb.co/cyZYOy/DSC_0015.jpg (https://ibb.co/jBfUwJ)

I replaced stock heatsink pad with paste instead to see if there are any temp gains towards it(yes, temp got down by 3 degrees, from 41c to 38c average)

https://preview.ibb.co/nMLq3y/DSC_0020.jpg (https://ibb.co/mg1KwJ)

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Overall image of the hashboard`s backside:

https://preview.ibb.co/nf8ciy/DSC_0001.jpg (https://ibb.co/cXHEVd)


VRM:
BM1680 voltage(~900mV) seems to be maintained by a combination of Intersil ISL68127 Controlling 6 units of ISL99227(Chip states: 27F 78AO, so this is only my best guess because of 68127 datasheet) in a 3+3 Configuration to supply 2 BM1680 chips for each ISL68127 unit.

https://preview.ibb.co/f84Tqd/DSC_0011.jpg (https://ibb.co/cJKHiy)

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Some more random images of hashingboard:

https://preview.ibb.co/f38A3y/DSC_0018.jpg (https://ibb.co/cyx3Oy)


https://preview.ibb.co/dn7bbJ/DSC_0017.jpg (https://ibb.co/hYbDOy)

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Stock heatsinks with pads.. Is really pads a good solution for 25w of heat dissipation? Im more on the side of using paste instead and lowering fan speed, with one fan and paste i maintain a temp of 38c with a surrounding temperature of 25c.

https://preview.ibb.co/dKDzwJ/DSC_0022.jpg (https://ibb.co/cAmKwJ)


https://preview.ibb.co/hbyXGJ/DSC_0021.jpg (https://ibb.co/d8dXGJ)


The BM1680`s are by far not the type of ASIC chips that we are used too from Bitmain, these chips can be used for various applications. The miner is noisy as hell, both fans are always at 100% with no regulation what so ever when its mining. At startup before it starts to mine it is PWM regulated, i hope that Bitmain in near future will release better software/firmware for these miners that will allow them to be overclocked and that the fans gets better/proper regulation.

Thanks for taking these pictures, this is always something neglected with new miners and I’ve been looking for a look on the internals of the B3 for quite some time. Confirmation that the chips in the B3 are indeed Sophon chips is also nice, but I also agree that it’s odd and unfortunate that you cannot control the fan speed of the B3s while they are mining. They don’t use that much power after all, and not much should be needed to cool them.

Thank you very much for the inside look, I was pretty damn sure they were sophon chip but didn't want to risk warranty to open it.

About the fans: since they are unregulated, I removed the back one completely. The miners will take a longer time to start but will eventually start hashing away normally.

I didn't see any increase in temperature, however the noise has been reduced at least 40-50% and the high pitch squeal is gone completely. I never liked the push/pull setup all miner manufacturer uses anyway, it's stupid.

Hi, what is the distance between the heatsink's holes ?


https://i.imgur.com/IHxZfGW.png

Eliot

Thx for pics and info.

I'am not the big tech guy, but i'am curious about some things.

- Could it be that the same or similar design is used for the Z9 and E3 that are coming?
- What is the purpose of the 2GB RAM exactly?
- The Processor is supporting 16GB RAM each if i remember right, adding it, what would be the purpose/gain of it?
- In case the upcoming Z9 and E3 use again these BM1680 processors, could it be that more RAM is used on these?

Hi Eliot!

Did not measure distances and i dont have the miner available at the moment, if i pop another one open i will check.

I have no idea whether Z9 or E3 will be using the Sophon chips, but its not unlikely that we will see these chips in the E3 at-least.
The 2GB memory is located on the controller board and supplies the chip that contains linux.
If the Z9/E3 uses this, yes RAM will/must be added if they intend to use BM1680 chips.

I replaced rest of heatsink pads with paste on the other hashboards, and its overall temperature is about 2-3c lower than the two other B3`s.
https://preview.ibb.co/bNPiad/Screenshot_22.png (https://ibb.co/bV7fMJ)

Keep in mind that this heatsink paste i use is by no definition "high-end" type, rather low-end that i have been using for transistors.

Hi!

Thanks for a lot for the pictures and info!
I always love to see such infos!

btw, are there any PICs used (as on L3,S9,A3, etc...) on hashboard?
as I see a possible coding interface.

Thanks a lot and bye, FNT

Been a while since I've had a Bitmain product but this seems like a huge step up to the Antminer S1
And S3 they used to release back in the day.

Back then their PCB were much simpler to understand. These seems pretty high tech. Don't know if that's considered a good thing since it might get more issues with reliability.

The fan issues can be easily solved if you guys just attach them to a 12V source and use a resistor or some potentiometer. However no idea if there is a sensor and if it doesn't detect a fan, it will fail to hash.

I did not look any more at it, but from reading BM1680 datasheet i guess there is direct communication with host/controller board, and probably the BM1680`s are daisy chained in pairs.


Using resistors and/or potmeters on these fans would produce a lot of heat, but a simple external PWM controller is possible since these fans are controlled by PWM signal. Not sure if the machine checks if fans are alive while running.

Those 8 holes on the left and the right are probably 0.1 inch apart, measure this on the photo and measure the spacing between the holes you need.
They are going to be round number to 1 mm or 0.1 inch most likely.

Just a thought

Guys did you try overclocking B3 to squeeze more from it ?

Thanks for the opening  ;D The inside looks really complicated and bitmain have really knowledge of this stuff...

Bitmain warranty ?  ::)

Hello,

we are already hundred angry buyers, please come to us, we ll fight against that scam!

https://discord.gg/qcQXFcj

Really nice post OP, I love some good hardware porn. It does look good inside and the build quality is fine but I could see in some other threads buyers are not so happy about it.

You win some, you loose some.. Usually the GPU`s being screwed over, apparently now its the other way around :P

Yes, this seems to be one of the rare cases where the tables have turned. I feel sorry for those that invested into this miner and can't get profit from it or break even.

Do you have any idea as to the die size of the BM 1680?