1GH/s, 20w, $700 (was $500) — Butterflylabs, is it for real? (Part 2)

[kano]

i really wonder about that 500% efficiency, i'm thinking about making a bounty to anyone who tells me wtf that's all about.

What I wonder is the following: can a pool detect that the device is checking not an every number in the nonce range but instead every n-th number in the nonce range?

Instead of doing hashing for 0,1,...,4294967294,4294967295 it would hash only (say) 1,3,...,4294967293,4294967295 or some other similar scheme of skipping through the nonce range?

You gain nothing from not checking all nonce values.
However if you only check one nonce per getwork, you're gonne be doing a LOT of getworks so slowing down your hash rate in a big way

The reality of it is that, with a standard 1 difficulty share pool, on average you will find 1 share per 2^32 nonces you check.
Skipping them makes no difference.
... and before anyone comes up with the stupid idea of stopping the nonce counter when they find a share, makes no difference either.
A nonce range can have no shares or could even have 2^32 shares.
It's all random statistics.

For those having difficulty understanding - consider this:
Say you have a coin and want heads when you flip it.
Once you flip heads you can either ignore the next one or include the next one.
Either way will make no difference to how many heads you are expected to find per the number of times you flip the coin.

The well known definition is actually Gambler's Fallacy http://en.wikipedia.org/wiki/Gambler%27s_Fallacy
Just coz you find an answer in a truly random event, it will not effect the next time you will find an answer.

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[DeathAndTaxes]

What I wonder is the following: can a pool detect that the device is checking not an every number in the nonce range but instead every n-th number in the nonce range?

Instead of doing hashing for 0,1,...,4294967294,4294967295 it would hash only (say) 1,3,...,4294967293,4294967295 or some other similar scheme of skipping through the nonce range?

That would significantly reduce efficiency not boost it.  Skipping nonces means you would on average find half the shares per getwork.

Efficiency isn't that important.

ALL efficiency means is (# of shares per get work). 
5.0 efficiency means you find 5 shares per getwork request. 
1.0 efficiency means you find 1 share per getwork request. 
0.5 efficiency means you find 1 share per 2 getwork requests.

Without ntime rolling efficiency > 100% is impossible (on any hardware).  Pool operators like high efficiency (and botnets that don't use a proxy have horrible efficiency) because per GH/s or TH/s the pool server needs to do less work with high efficiency miners.

[kjlimo]

Icarus is for sale, he is on batch 3... i don't know if I am helping or even if this is what you are talking about...

Icarus specs:

speed (MH/s): 380
$: 569

Costs as much or more than BFL, gets half the hashrate.  So, I want to know where I can buy 235 MH/s @ 9w for $120... I'm waiting for that info, not the advertised Icarus specs.

The 500% was explained by Kano, which was pretty much what I theorized.  Why is your 7970 not getting that? I dunno, I don't have one to test with, but I suspect it may have to do with the fact that you are using multiple threads on the 7970 and the BFL uses a single compute thread cranking at 832 MH/s, so it blasts through the entire work space at that speed, instead of splitting it between multiple workspaces.  Then it rolls the time and starts again, giving the efficiency seen. So when it's time to submit the work back, it's already rolled through 4 or so blocks on the single thread (and thus a single getwork), where your 7970 has rolled through 4 blocks on 4 threads with 4 getworks.

  

Agreed, Butterfly labs has the convenience of selling a nicely packaged pretty much "plug & play" option.

RPH has been building his own units for $1 per mhash and they have good voltage.  I think he's talking from experience rather than from theory...

And yes, the small time home grown solutions are charging a premium for their electrical efficiency they bring to the market place

[kano]

Icarus is for sale, he is on batch 3... i don't know if I am helping or even if this is what you are talking about...

Icarus specs:

speed (MH/s): 380
$: 569

Costs as much or more than BFL, gets half the hashrate.  So, I want to know where I can buy 235 MH/s @ 9w for $120... I'm waiting for that info, not the advertised Icarus specs.
...

$120?

Icarus IS tangible and Goat wasn't talking shit ... as you said.

I simply stated that the person I've been chatting with is getting roughly 235 MH/s at 9W.
(and he is getting that with cgminer ... modified for the Icarus - the code may end up in cgminer soon but you can find it on github)
The power cost per MHash is definitely WAY lower than a BFL (almost 1/3)
Someone else can work out if that really matters or not.

The person is getting 50~60 Icarus devices soon ... apparently.

[kano]

Icarus is for sale, he is on batch 3... i don't know if I am helping or even if this is what you are talking about...

i have a bounty for the first person to get a BFL single and that has not been claimed yet.


also ill pay 5 BTC to anyone who full helps me understand why this things gets 500% eff when my 7970 only gets 99%...

ill pay much much much more to get my 7970 at 500%

Run cgminer on EMC (with -g 1 and probably -I 11) - how much more will you now pay me over the 5 BTC I'm obviously not gonna get
Edit: Oh yeah you need SDK 2.6 and -k poclbm (but I think the latest version works out it's a 7970 and uses poclbm anyway when you have SDK 2.6)

As stated already but I will repeat - Efficiency makes no difference to how much BTC you get.
It is just the number shares you return vs the number of getworks you do.
It still takes the same amount of time to generate each share.
It's good for the pool if you only ask for a getwork on average every 5 shares rather than every 1 share.
It may be good for you also if your miner is ever waiting for work to do (i.e. is running below it's normal hash rate) but that should be rare if ever.

[2112]

That would significantly reduce efficiency not boost it.  Skipping nonces means you would on average find half the shares per getwork.

You gain nothing from not checking all nonce values.

Thank you very much for your explanations, gentlemen. I misunderstood the definition of efficiency.
I now understand that this parameter isn't that important and pools are mostly interested in it in a statistical average way.

[cypherdoc]

Video of the device?  What do you want the video to show?  A box with a red light? heh

Even though it could be doctored, maybe a video of the box hooked up to a computer with a display on the screen of mhash/s.

Also, a walk through from opening the box, hooking it up and getting the software running.

I realize that's a lot to ask, but it's certainly something I'd be watching right now if it was available.

that would not be too long to ask.  what would it take?  like 5 min?

[SysRun]

Video of the device?  What do you want the video to show?  A box with a red light? heh

Even though it could be doctored, maybe a video of the box hooked up to a computer with a display on the screen of mhash/s.

Also, a walk through from opening the box, hooking it up and getting the software running.

I realize that's a lot to ask, but it's certainly something I'd be watching right now if it was available.

that would not be too long to ask.  what would it take?  like 5 min?

We don't need an Inaba unboxing, we need a shipped device, tracking number anyone?, and an unboxing video from a customer (someone who has an actual production unit).

We also need some kind of communication from BFL.

[bulanula]

Video of the device?  What do you want the video to show?  A box with a red light? heh

Even though it could be doctored, maybe a video of the box hooked up to a computer with a display on the screen of mhash/s.

Also, a walk through from opening the box, hooking it up and getting the software running.

I realize that's a lot to ask, but it's certainly something I'd be watching right now if it was available.

that would not be too long to ask.  what would it take?  like 5 min?

We don't need an Inaba unboxing, we need a shipped device, tracking number anyone?, and an unboxing video from a customer (someone who has an actual production unit).

We also need some kind of communication from BFL.

I suggest you wait 4-6 weeks

They are waiting for Nvidia Kepler to be released before they ship these unicorns out.

Long con surely. STILL, nobody has a shipping number. Remeber 4-6 weeks last year in November ?

[kjlimo]

Video of the device?  What do you want the video to show?  A box with a red light? heh

Even though it could be doctored, maybe a video of the box hooked up to a computer with a display on the screen of mhash/s.

Also, a walk through from opening the box, hooking it up and getting the software running.

I realize that's a lot to ask, but it's certainly something I'd be watching right now if it was available.

that would not be too long to ask.  what would it take?  like 5 min?

I'm no producer, but I wouldn't be surprised if making a video (editing it & making it worth putting your name on) took a good 8-20 hours for a good 5 minute video.

Sure someone could throw the first 5 minutes of themselves onto the internet, but that's "a lot to ask" if the person doesn't want crappy quality videos of themselves online.

So either way, it's a lot to ask...

[kjlimo]

Video of the device?  What do you want the video to show?  A box with a red light? heh

Even though it could be doctored, maybe a video of the box hooked up to a computer with a display on the screen of mhash/s.

Also, a walk through from opening the box, hooking it up and getting the software running.

I realize that's a lot to ask, but it's certainly something I'd be watching right now if it was available.

that would not be too long to ask.  what would it take?  like 5 min?

We don't need an Inaba unboxing, we need a shipped device, tracking number anyone?, and an unboxing video from a customer (someone who has an actual production unit).

We also need some kind of communication from BFL.

I suggest you wait 4-6 weeks

They are waiting for Nvidia Kepler to be released before they ship these unicorns out.

Long con surely. STILL, nobody has a shipping number. Remeber 4-6 weeks last year in November ?

Wait, the first pre-order was made in November?  So you've only been delayed a month or two?  I don't think that's that horrible, especially if they catch up and deliver a good product.

The lack of communication isn't great.  I sent another e-mail last night trying to see if they have any planning for future deliveries.  No response yet, but I'm ok with a 24 hour response time.

Their previous response time was within an hour!

[MelMan2002]

Wait, the first pre-order was made in November?  So you've only been delayed a month or two?  I don't think that's that horrible, especially if they catch up and deliver a good product.

The first pre-orders were reportedly made some time before Oct 18...and even then the promised shipping was in 4-6 weeks from purchase date.

[SysRun]

I'm starting a 3 BTC Bounty for a shipping number followed by an unboxing video. Anyone else on board? Quote this thread and add your bounty amount so that we can keep a tally.

Its been 4 days since fred0 was told shipments would start and we haven't seen a single tracking number OR unboxing video.

[simonk83]

Its been 4 days since fred0 was told shipments would start and we haven't seen a single tracking number OR unboxing video.

Here's my latest (this was a day or two ago):

Just to confirm, I've got your account marked for packing.  We haven't got to your unit position shipment yet.  We're obviously slow with the hand assembly, but we're very close.

[Inaba]

I think when someone sees what they mean by hand assembly, if you've ever done anything vaguely like it, you'll understand why it's a slow process.  I know I wouldn't want to be doing it...  They also do a burn in of the unit to make sure it's functioning, which takes time that can't be avoided.

[imsaguy]

I think when someone sees what they mean by hand assembly, if you've ever done anything vaguely like it, you'll understand why it's a slow process.  I know I wouldn't want to be doing it...  They also do a burn in of the unit to make sure it's functioning, which takes time that can't be avoided.

If all of that is true.. so be it.  But promising 4-6 weeks if you know its going to be longer than that is wrong.

[Inspector 2211]

Its been 4 days since fred0 was told shipments would start and we haven't seen a single tracking number OR unboxing video.

Here's my latest (this was a day or two ago):

Just to confirm, I've got your account marked for packing.  We haven't got to your unit position shipment yet.  We're obviously slow with the hand assembly, but we're very close.

So, it seems you're in the first batch.
May I ask when you ordered it?

[simonk83]

Its been 4 days since fred0 was told shipments would start and we haven't seen a single tracking number OR unboxing video.

Here's my latest (this was a day or two ago):

Just to confirm, I've got your account marked for packing.  We haven't got to your unit position shipment yet.  We're obviously slow with the hand assembly, but we're very close.

So, it seems you're in the first batch.
May I ask when you ordered it?

Towards the end of December, so I guess anything before that is in the first batch

[Inaba]

If all of that is true.. so be it.  But promising 4-6 weeks if you know its going to be longer than that is wrong.

At what point of this thread did it lead you to believe they knew it would be longer?

[kano]

If all of that is true.. so be it.  But promising 4-6 weeks if you know its going to be longer than that is wrong.

At what point of this thread did it lead you to believe they knew it would be longer?

Maybe for him about 12 weeks after they first promised 4-6 weeks?

Or ... for me when Sonny's email was posted proving that the reason the first version didn't do what they advertised and accepted money for, was that it didn't exist (it was a simulation) back when they were advertising details and accepting money for it

(also they are never gonna live down that 10 years experience statement ...)