Topic: BITMAIN launches 4th generation Bitcoin mining ASIC: BM1385 - page 11. (Read 39340 times)

Remember the guy who killed the golden goose ...  they don't want to be that guy

Makes you wonder what the price of the first 16 nm miners are going to run to try and make up for the cost, I think 16 nm may be the end of the home miner for a couple of years.

Shifting part of the risk onto the buyer and getting money upfront.

If cloudmining is making profit why don't owner just mine theirself ?
Why do they want to sell to you guys ?

It is great test , how long you run it like this , I am thinking the stability of using lower version of controller .

6, 7, 9, or 10 presumably. 100k USD sounds affordable


My respect for what you do for this community notwithstanding - I think you're wrong on this one. S1 showed up at the end of 2013 - so perhaps you meant early 2014 there. Yes, S1 and S2 depreciated quickly. However S3, S4, S5 and perhaps even the last runs of the S2 could be used for a couple of months and sold for near their original price without ripping anyone off, due to all sorts of interesting scenarios with difficulty and exchange rate changes. So that's 3:2 against your historic argument, and the future is anyone's guess so let's make it 50:50

Again, you're taking an idealistic view of this. Purchase price minus "depreciation" must be your sale price? That's almost never the case. As someone already mentioned, if they list it as an auction on eBay and describe the condition properly and don't advertise it as a free money making machine - that's a fair game. Buyers electric cost, risk tolerance, future outlook, $25 eBay coupon, preference to buy locally instead of from China, and a bunch of other factors can affect the end price.

The rolled vs. unrolled isn't a fully resolved choice. The losses and noise in the very long lines that drag the signals over 15 SHA-256 rounds are quite significant. I think the bitfury approach of routing hashed words in one direction and constant SHA coefficients in a perpendicular direction gives overall savings over trying to squeeze combinatorial optimizations after fully unrolling. Most of the combinatorial optimization gain is achieved by SHA-256 round pairing, i.e. 32 round-pairs instead of by-the-FIPS explicit 64 single-rounds.

I did not do a full analog modeling of both choices (rolled/unrolled) for SHA-256. But I've done something similar in the past that was bound by the speed of carry-look-ahead adders. I actually doubt that anyone here on this forum (maybe with exception of bitfury) did the required tradeoff analysis. My scientific will-ass guess is that Bitcoin miner has a possibility of being an example of one such circuits where leaving things rolled will be of great benefit. The very high toggle ratio (only -6dB below the theoretical maximum of a ring oscillator) will probably benefit from using some sort of SCL (source-coupled logic) or CML (current-mode logic) instead of the garden-variety CMOS bang-bangs that every CAD monkey throws at the Bitcoin mining problem.

People do fully unrolled hashers because the logic synthesis tools use heuristic place & route algorithms that don't converge or converge extremely slowly on the rolled designs.

As far as I understand the full DRC compliance at 28nm "mature" process is very, very conservative. I don't have any exact numbers handy, but the assumed gate  error ratios for a "digital" manufacturing process are way too high for Bitcoin miner that can easily tolerate a percentage point of errors. Violating some of the DRC to shed the unnecessary margins is one of the simplest ways to save power, after the obvious things like dropping JTAG and other testability overheads.

Re-reading your first sentence, I don't really understand the part
Could you restate what you had in mind?

This new mining chip is more energy efficient. Every new model is even more efficient than the previous one. Can't wait for Bitmain to release the Antminer S7. This is something I would like to buy...saving my money to buy a pair of these 

You have completely the wrong view of full custom, a rolled design would be a really dumb idea for a modern mining chip and very area inefficient, the customisation involves only two circuit elements, but I'm sure you know that. Not rocket science at all, no magic, and very little risk if you have some respect for semiconductor physics. DRC is there for very good reasons which again I'm sure you know, and only an idiot would even consider violating them.

That isn't truly fair, if there is someone who believes in the altcoin or wants to try and gamble on a coin thinking they are Mr.Daytrader I don't thinking selling any altcoin is ripping somebody off. Now if you're a scumbag who sells 1 doge on ebay for 1$ then yeah you're being a scumbag and scamming people on eBay who don't understand what they are buying, but on an exchange they know the risk and you do to. (mining an altcoin that could easily drop in value is riskier)

That's pretty sweet. Looks like you put together more like what folks would have a thought an S5+ would be, before pictures of the "3 module monster" appeared. I thought there was a 16-pin -vs- 18-pin mismatch on the cables between the controller and the hashing board. What happened there?

Have you got any power measurements? I expect it would be roughly 1150W at the wall?

Yes. I did.

S5 controller with S5+ miner

The added 'risk' is because for the first time they are getting outside the 'standard cell' design flow.

I have doubt that the new design is truly full custom. Their previous designs were simple unrolled hashers. True 'full custom' optimized design would be rolled. And switching from unrolled to rolled would involve redesign of the I/O protocol.

My bet is on them purchasing a custom standard macro library: lower-power by lower-area and lower-noise-margins. Sort-of like bitfury did for his first chip: 55nm-drawn transistors in the 65nm-nominal process.

Such a 'extra-low-power' library may be violating some default DRC's (design rule checks) of their foundry. Thus the foundry makes them explicitly waive DRC conformance warranty with their mask order.

S5 controller



S5+ controller



The same space, but the temperature difference is 10 degrees Celsius.

It seems to be impossible for the Bitcoin miner designers to hire the knowledgeable people. Do you know of any Bitcoin mining ASIC project that doesn't look like a student project or a quickie hack job?

Thus far only ASICMINER acknowledged (very early) of being unable to hire or contract anyone with power/analog ASIC experience.

@dogie

Of course, an S5 isnt obsolete when the S7 has been released - you have your points here.

@Tupsu

Thanks for the pics- that looks cute. So it is quite possible.

So did you know for sure about the S2 uprade kits not being produced and held back a response?  They only failed do to Bitmain not following through on not one but both announcements.  It's a shame to let a good case and design that's accomodating and easily upgradeable die. 

This was discussed a while ago in design, and the conclusion was that its not actually that desirable for the same reason that S2 upgrade kits never appeared. By the time the next generation appears, the previous generation is still mining away perfectly happily and so you can't immediately replace those hashing boards.

Ie if the S5 was modular to the S7, you'd still buy a full S7 because any S5s you had would still be fine to run for the foreseeable future. No one would scrap their S5, they'd simply run both or sell the S5.

You want  standard ?
Let me give one free.

Tested. S5 + works with  S5 18 pin controller board.  If this is not the standard?
You do not even need to change the software.

Now you can do from yor  S5+  three miners .