I don't know if its a bug or a generated development but when you reload the page after you have sent the merit(the merit sent! page). The system automatically sends another merit to the same user. It will be great if this can be improved as merits as of now are deletable so such problems will lead to loss of quite some sMeirts.

I don't know how many of you have been following the post from Great North Data, https://bitcointalk.org/index.php?topic=1512967.0, it's essentially
their blog of setting up a new data centre in Labrador, Canada and it makes for very interesting reading, not just about the centre but about life in
Labrador. It's very well written.

A lot of the questions from forum users are about power costs, not surprising since this has a major effect on mining profitability. There is an awful
lot of misinformation on the forum about real world power costs but the bottom line is that there are a lot of countries and locations in the world that have
expensive electricity, and so profitable mining there is impossible. Hosting services can be used of course, but they are very much geared towards
users with multiple miners, for instance the GND guys look for a minimum of 10kW (7 S9's) and they are not alone, there are no good solutions for
someone with a single mining system.

This is a problem I've been thinking about for a long time, there is no easy fix but I feel there is a good commercial opportunity to set up a hosting
centre where there is abundant low cost power to serve single (and multiple) unit users by exploiting economies of scale. From my research the best
location by far is Iceland, basically because they have the ideal combination of low temperatures, very cheap power and a truly first world business
attitude and legal system. To access the best rates you need to be taking a load of about 50 - 70MW, ie 2.5x Bitfury's centre in Ukraine and I'm guessing
from the weight of their power transformer that GND have about 8-9MW. The cheapest way to construct a data centre with this level of power would be to
use containerised systems - they are much cheaper than permanent buildings ($15 per square foot versus around $170) and to expand you can simply
add new units. They are also usually exempt from the health & safety regulations that apply to permanent indoor sites and will be easier to get
planning permission as they are not permanent structures.

The setup costs for such a secured data centre site with a 63MW main power transformer, 16 distribution transformers (2 per container), cabling,
switching, protection and 8 containers (with inbuilt 12v supplies) each capable of hosting 2100 s9 sized miners (or equivalent volume) would run to around
$3.9 - $4.2 million, the main transformer runs at 80% of full load and is capable of powering 16 containers. At this scale it's entirely possible to offer
power to single unit (1.5kw) users at around 4.5 - 6 cents per kWH, if there are enough of them ie around 16,000. The rates include 2 x 10Gb/sec leased line
internet connections and 2 technicians available 24/7, the data centre would take 9 months to reach operational status. Assuming difficulty increases at 2%
per month and that the bitcoin price remains at $600, an S9 installed in the centre in July 2017 at a network rate of 2250PH would pay for it's purchase price
($1600 - no power supply would be needed) in about 15 months at 6 cents per kWH and 13 months at 4.5 cents. I know there's shipping, import duty etc but
I'll cover ways to minimise that later.

Financing such a venture is another matter altogether although there is a good opportunity here for a forward looking company thats willing to swap margin
for volume. This centre could host older equipment that been paid for and extend it's working life, there's also the possibility that miners could buy into
a contractual agreement that gives them a long term guarantee that power will be available for them at a fixed amount above the actual cost price.

Comments?

Firstly, congratulations to Bitfury on getting their chip working. Considering the number of asic mining chips that have failed to deliver in one way or another, it's always good to see a new one coming along.

However, I think they are being somewhat 'economical with the truth' in terms of the actual performance of the device, and that makes me a little suspicious of what they say. I'm especially wary of their power consumption figures, or should I say lack of said. Yes, they are given a headline figure of 0.06 J/GH, which is a meaningless metric as it should be J/(GH/sec) for any meaningful comparison, but then they claim 40Gh/sec at the same figure. Still no mention of clock speed, but we'll leave that just now.

Many month ago Guy Corem of Spondoolies posted that sub 0.1 J/(GH/sec) was possible in 28nm with 'extreme' design  and he is absolutely right, in fact Bitfury get their low power consumption with a very low voltage and presumably a very low clock speed.

This is hardly breaking edge design, especially in 16nm.

Bitfury go on to say the device can operate up to 192GH/sec but fail to mention the power consumption (or clock) at this speed. Why? If this device is as energy efficient as they say them surely it should be at least sub 0.1 J/(Gh/sec) to compare with what Bitmain can achieve in 28nm? Stepping own two process nodes (28 to 20 to 14/16) should result in energy saving of at least 50% so why hide it unless the actual figure is higher than expected? They also convenient ignore to specify the J/(GH/sec) at 55 Gh/sec, mentioning only 'convergence to a plateau' (from 40 Gh/sec) whatever the hell that means.

Then there is the matter of the die size. Again no mention of this in Bitfury's press release, but one of Guy's extreme design techniques involves using a lot of silicon area, so I'm hazarding a guess that this little beast is probably a good deal larger than one might expect. I'm taking a guess that the chip is running at around 1Ghz when producing 192 GH/sec in which case a cell based design would come out at around 25 square millimetres, 5mm on a side. I'd love to know how this one compares, naturally a bigger clock speed means a smaller die.

I don't have any Bitfury products or interest in their company save what they choose to print, so I have no axe of any kind to grind with them. They can write what they like, but please don't try to mislead or misinform people, I know they are not in the consumer market any more but take a leaf out of Spondoolies book and give people comprehensive REAL figures of what your devices can achieve in practice rather than carefully chosen 'sweet spots', especially if you are planning to ask them to part with money. That's what the real engineers do.

I'm surprised no one has picked this up - 

https://bitcoinmagazine.com/articles/bw-to-launch-nm-chip-and-miner-for-general-population-1445278227

BM plan to make a 14nm chip, all the usual nonsense and weasel words including this from the journalist:

"The quiet, behind-the-scenes juggernaut in bitcoin mining, Bi Wang (BW), is announcing the release of its 14nm chip that the company believes is at the cutting edge of bitcoin mining equipment"

Oh yeah? I believe it isn't so who is right?

This device isn't due until Q4 next year, and they will only sell their miners in batches of 333 pieces, 3TH each at $250 or $0.08 per GH. By the time they arrive the hash rate will likely be over 900 petahashes so I'd love to see their financial projections for this project. For the buyer its not a great deal even with Btc at $300 they are likely to make about $1.8 a day, less electricity costs (about 50 cents a day even at $0.05 per kWh) and you can bet that the hashrate will only go higher once all their pre orders get dumped on the network.

So if you fancy financing their chip and future profit, why not get your (virtual) wallets out?

Just had a visit to Cointerra site where they posted, on January 14th,  that they had a fully built up box working at 1.62TH, or " a little over 80% of (their) performance target.

They also said that their engineers were "making continuous tweaks and refinements each day to improve the power efficiencies on the board to increase performance". Well, they said the engineers had one die on the package running at 132Gh/sec on the 7th of January, so four of them should meet the target spec. They would have known within hours if there was any kind of problem, which there clearly is.

Maybe I'm just cynical (and I am) but 20% seems an awfully large gap to close with 'tweaks' unless someone has seriously screwed up on a major part of the design. I haven't bought one of their rigs, but I'm sure that every one of their anxious customers would gladly sacrifice a bit more power consumption just to get their paws on their purchases. Remember that Cointerra have $1.5 million of Private Equity funding - which they obtained before the public got in on the act - and I'd hate to think that any delay had been introduced into the supply of rigs to the public customers as a consequence of the presence of this funding.

Remember that these guys are already running late and if there's still 'tweaks' to be done at this stage, the December buyers will be lucky to see their rigs before the end of January; small 'tweaks' might mean changes to printed circuit boards or different components to be sourced, either of which might be $2-3 changes but may take weeks to source and/or change.

Perhaps one or two of those customers might like to ask Cointerra some very pertinent questions about what the problems are? Don't want another Hashfast, do we?

Sorry if this has been discussed before, but I'm buggered if I can find any threads that give me the answer.

Lots of pages refer to the 'double' sha256 hash in the bitcoin hashing algorithm. However, there seems to be a concensus that most miners only perform the inner hash once, then use the output digest from it again and again; indeed in the Getwork wiki, it actually says:

"running a full SHA256 round is generally inadvisable. Most miners will precompute the SHA256 "midstate" from the first 512-bit chunk of data, and only repeat the 2nd SHA256 round with the final 512-bit chunk (which contains the nonce). "

This may be out of date, and I'd appreciate some advice as to whether it is true or not.

Question is:

When an asic supplier quotes a hashrate, is it based on a 'true' double hash (taking twice the time) or an 'optimised' one as described above? It makes a big difference, I've only so far seem one supplier - Bitfury - mentioning a double hash. I recently came across the stats of the BFl chip - what a monster! 7.5 x 7.5mm2. That gives a useable chip area of 6.9 x 6.9 or 47.6 mm2. On TSMC's 65nm process, raw gate density is about 850k gates/mm2, so this device probably has a utilisation of 80 - 85% or 32 - 34 million gates.

BFL say there are 16 unrolled pipelines on the chip. If they are 'single' length, ie 64 sections, then each section is roughly 33*10^6/(16 *64), ie 32000 gates (or 16000 if a double length pipeline is used). Yes, I know there is control logic and so on, but it shouldn't take more than 500k gates.

Either way, they seem awfully large, by a factor of 10 or 5. Possibly due to an FPGA conversion?

Anyway, this is bugging me. Can anyone help?

Thanks.

Knew I'd find this eventually:

"An ASIC Design for a High Speed Implementation of the Hash Function SHA256 (384, 512)", Dadda, Machetti, Owen (2004)

These guys came up with a re-timing pipeline which increases Maximum Clock Speed on a regular SHA engine by 36%. No new algorithm - you cannot 'improve' the existing one, this is simply an exercise to reduce critical path delay on an ASIC (not an FPGA)

So to any of you that are prepared to swallow the shite that KNC put out: Beware.

I'm not saying they are scammers, but they are dishonest with their information, to put it mildly.

Read into that what you will.

Hi all,

Just joined after a look around. Read through some of the posts regarding new mining companies, and this one caught my interest- kncminer.

Had a look on their site, and nearly burst out laughing. Seem to think they can change instantly from 40nm to 28nm technology (in standard cell, no less) and get a prototype out by September;

CRAP

Have a 'special' algorithm that speeds up SHA-256 by 30%. Oh yeah? On a data dependency algorithm? Have they got a time machine?

CRAP

Are actively asking their users if they would like a Litecoin asic when they haven't even delivered a Bitcoin one. The two are not remotely similar. and a Litecoin asic is going to be HUGE due to the memory requirement.

CRAP

One crap is ok, everyone can be optimistic or makes mistakes. But three?

Oh, and their wattage figures are way, way out; for once, too high. For example, their 'Saturn' miner will consume a maximum of 500W. For a 175GH asic based design on 28nm? It's about an order of magnitude too high. And water cooling? Guess what -

ANOTHER CRAP

Perhaps it's all down to the 30% extra hash power from their special algorithm?


***** ADD ON INFO **********


According to KncMiner's site, their 'Mars' box costs $2795 and contains 48 Altera Cyclone IV FPGA's 115k LUT version. That equates to just under $60 each. Are they getting them off the back of a lorry?

Cheapest price for 60 units on Altera's own site is $315 EACH, so even if they're buying them in the 10's of thousands, they are NEVER going to get a price 5 times less than this! For them to make the machine and make a profit they would have to be buying them at less than $30.

And since they are so fond of 28nm technology, why not use the much faster (and cheaper at $209) Cyclone V?

Can anyone else see something wrong with this picture?

BTW, I reckon a properly routed Cyclone V could do 2 -3 GH with just one unit. And no water cooling.