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The order book has opened for Cairnsmore1 single and dual versions. We will ship these from July but are taking pre-orders now and there is a launch discount on orders placed before the end of June.


Dual version GBP £400 / US $640 / 520€ (discounted GBP £300 / US $480 / 390€).

Single version GBP £300 / US $480 / 390€ (discounted GBP £250 / US $400 / 325€)

More detail on http://www.enterpoint.co.uk/cairnsmore/cairnsmore1.html.

Yohan

The other thread (https://bitcointalk.org/index.php?topic=78239.0) implied you were selling the quad version for $640.  The unit pictured also looks like a quad chip design.  Is there a mistake?

That is a picture of quad. We have not built a dual or a single as yet. The $640 for the quad is only until the end of June.

Thanks, I misread and was confused by the full price of the dual equaling the discounted price of the quad.

Something like 800-1000Mh/s on the quads?

That's £300, but on top there's VAT to pay ? so £360 for around 400Mhash ?

Power consumption?
If a single chip absorbs 12 x 1.2A, about 15W x 4= 60W ? and remain all the components?

Have you guys actually run a Bitcoin bitstream on these yet?

I find it very hard to do a pre-order without even ballpark specs from a working unit.

The isn't as cut down as we might have achieved with a fully optimised design but the upside is the standard PCB between all of the Cairnsmore1 variants and common components. We also get to test one PCB design for three products. With the sectioned power supply approach of the board we do get to leave off the 12A regulator circuits when a FPGA position isn't used. It's also entirely possible that the dual and single options will return a slightly higher performance per FPGA due to the same PCB taking less heat.

We could also do things like remove the clock generator and some of the power options to save a bit more but we have left those for flexibility. There isn't much we could save on the PCB by doing custom PCBs for duals or singles. The numbers that we are building the quad in gives us a good price on a PCB that was engineered in the first place to be cost effective whilst also designed for performance. Once we have the performance numbers I hope that will be proven out in hard facts.

Yohan

interested... when I see specs  ;D

Why do you consider BFL as being "shady" ???

I really don't understand. They have 10 years experience in FPGAs too.

Only disadvantage is high UK VAT import duty cost ...

They may have 10 years in the business but the reason I have always thought they were shady is money first then sometime in the future we will ship you boards and from their track record so far can't even meet the shipping date delays shown on their web site 6 months into it. These boys here when I pre-ordered sent me back email confirming the pre-order and saying when your boards are ready to ship we will bill you, the way it should be done IMHO..


Well they say they are going to be similar to the Icarus boards in performance and hopefully once tested it is confirmed so perhaps even more than that if they get ahold of buddy to work something out with to use it who has the 245mh/s bitstream for them same chips.

You're joking, right?

Let's search https://wyobiz.wy.gov/Business/ViewCertificate.aspx for their business standing:

I think you got your numbers mixed up there its 1.2v @ 12A. 12A is just how much the power supply can feed to the FPGA.... How much the FPGA actually uses depends on a lot of factors such as clock speed, the bitstream, I/O's, and many more.

This is one big difference that you will find with FPGAs and a big advantage over GPUs especially when loading isn't constant for whatever reason. A XC6SLX150 FPGA can run from a few hundred mA when an easy design is loaded or throughput is reduced. The actual current depends highly on the clocking rates and the design loaded. From what I have seen the best GPUs still take about half the power when lightly loaded.

We selected 12A capability given what other boards seem to use i.e. 8-10A. Runnning in the 8-10A zone also works with our regulator choice and it is in a better efficiency band than when running at 12A.

In the unlikely occurance of a fault our sectioned power also allows a faulty section to be turned off and also limits damage should a short occur. It would be much worse if we had a single 48A supply and that got shorted also taking down the whole board at the same time. 48A tends to vapourise tracks and do significant damage to anything on the current path.

Yohan

Waiting for some hashing numbers to be posted...

[subbed]

A lot of people are requesting this feature, and I hope you think about this for future products: use programmable VRMs. A lot of people want to undervolt their FPGAs to increase efficiency at the end of their effective mining lives and it would increase sales over the BFL juggernaut.

Who would buy a single or double?

Quad - $640 = $160 per FPGA (however many MH/s tht is)
Double - $480 = $240 per FPGA  (50% higher cost per MH/s)
Single - $400 = $400 per FPGA (150% higher cost per MH/s)

Am I missing something?

Quad - $640 = Temporary pricing.  Ends May.
Double - $480 = Standard price
Single - $400 = Standard price

You sure about that?

From OP

I look the discounted to be pre-order special pricing so $640, $480, $400 is apples to apples right?

Based on their quad thread.
https://bitcointalk.org/index.php?topic=78239.msg870881#msg870881

At 640 USD through end of June (not May).  Price to go up 50%.  Some confusion on this thread.  Not sure what's up.

I don't think there is any confusion.

There is pre-order price:
Quad - $640
Double - $480 (50% higher per MH/s)
Single - $400 (150% higher per MH/s)

There is also the post June price
Quad - $960
Double - $640 (33% higher per MH/s)
Single - $480 (100% higher per MH/s)

Either way the question stands who would buy a Double (or even worse a Single)?

When MH/$ determines payback period having 33% to 150% longer repayment kinda makes those products nonviable.
If hypothetically you could break even on a Quad in 12 months it would take 30 months with a Single.  Is there really a market for that?

We don't expect the market for the singles and duals to be anywhere as big as the quads. There are a lot of static costs in building these boards which don't change between the 3 versions and the quad is always going to look better and yes we are going to look at something bigger and more on that later. You will just have to wait in anticipation before we show where we are going.

We have done the singles and duals more as a technology tester for people that are in say the GPU world and don't want to spend a huge amount of money trying out something rather than them being the ultimate solution.

As to shaving voltages we are already testing something along those lines on a different product that uses the same regulator circuit as Cairnsmore1 and it might make it to Issue 1.2. More mundanely we are going to do some performance testing against voltage settings and then set the regulators at where we think is maybe the best point in production. Whilst there is something to gained out of this there are places where we think that much more can be achieved and more on that will come in the coming months.

Scribe

^d