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2641  Bitcoin / Bitcoin Discussion / Re: Has the NSA already broken bitcoin? on: October 21, 2013, 04:32:56 AM
ECDSA is not the same as Dual_EC_DRBG.   The vulnerability is with Dual_EC_DRBG not the entire ECC concept.  Actually the speed at which the crypto community sounded the alarm on Dual_EC_DRBG should be seen as a positive sign.  It was/is an obscure algorithm with no real widespread usage and the flaw was found and published internationally in the span of a few months.   
2642  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 21, 2013, 03:41:55 AM
crumbs there is a finite amount of available space to make a rackmount unit.  You design a rackmount unit with better airflow, buy modules from HF in bulk and then resell the package.  I think you will find it is harder than it looks.   Putting radiator in the back would be an "easy" solution except you only have 17" by 1.75 x U height inches to work with.  If the power supply is mounted on the back and the radiator is mounted on the back the radiator will be tiny, too little surface area to effectively cool 750W+.    To keep Delta T less than 10C over ambient you are going to need 1 to 2 cm2 of radiator surface area per watt (i.e 420cm x 120cm on 750W heat load) even with pretty high extreme airflow (3000 RPM pusher & puller fans).  There is only so much surface area on the back or front panel of a rackmount unit.

Sure if you don't want to compromise then build a massively expensive 6U chassis with straight flow power supplies and the entire rest of the back panel devoted to a radiator.  Of course when you do so you would price yourself out of the market and people will just buy the more economical solution from Hashfast or Cointerra.
2643  Bitcoin / Hardware / Re: HashFast launches sales of the Baby Jet on: October 21, 2013, 12:57:33 AM
It would certainly stand to reason, since they're apparently using a one-off run of Seasonics with a reversed fan in the newly-designed Sierras.

Unsubstantiated claims. 

HF reported signing a deal with SeaSonic.  The deal said nothing about a custom run.
Some people have speculated the PSU fan operates in reverse.  HF hasn't stated that.

Extremely likely the PSU are the same exact SeaSonic models you can buy from newegg.
2644  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 20, 2013, 11:46:46 PM
As far as PSs being fine with sucking on hot air, i'm not so sure.  Making them do it just because people were too lazy to think about proper air management is absurd.

ATX PSU are designed to intake from heated case air.  It isn't being too lazy.  A rackmount case is only 17.5" wide.   A power supply is 3.4" wide.  You would need to use a more expensive server (designed to have front to back airflow) power supply and then you would still lose 20% of your front surface area.   Removing 750W+ by watercooling is no small task and that means a relatively large radiator surface area.

Sure if you wanted to make the case larger 6U+ or only put 2 Sierras per case but those would be inferior choices IMHO.

Power supplies are designed to work at high ambient temps.   Both servers and PC intake cooling air from inside the case.   Some high end PC allow flipping the PSU to draw outside air but that is the exception not the rule.   SeaSonic puts a 5 yr warranty on their power supplies and they know 90%+ of the time it is going to draw in heated case air.  They are designed to handle that.  Actually it has become an easier engineering challenge as PSU become more efficient it means they have less of a heat load.
2645  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 20, 2013, 09:56:47 PM
Its also pretty darn stupid to pull air in from the back of the rack where everything else is dumping its heat. THe PSU would be breathing in warm air, heat it further, then dump that inside the cabinet where it cant get out.

The PSU (like evey PSU made) exhausts out the "back".  If installed as shown in HF model it would intake from the outside and exhaust out the back.  If you flip the PSU 180 it would instake from the inside and still exhaust out the back.
2646  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 20, 2013, 09:52:00 PM
What's funny about the whole layout is the radiators/fans are at the front of the case, dumping the hot air *inside* the case, making the PSs suck in hot exhaust when the PSs are flipped 180.

Every single rackmount server pulls in warm case air to cool the PSU.  PSU these days are highly efficient they don't need ultra cold air or high RPM fans.   A low airflow of hot (90F+) air is well within design spec.  It is a non-issue.  At 600W load and 90% efficiency you are talking 54W of heat.  It is more expensive (due to the amount of metal in larger heat sink) but they make passive power supplies because 54W in a space the size of a power supply is nothing it is less than a lightbulb in a space 10x larger.
2647  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 20, 2013, 09:48:51 PM
The power supply is a non issue.

Outside of datacenter.  Use it as shown in the photo.  Draw in cooler outside air, exhaust out the back.

Inside datacenter (w/ restricted side access).  Flip PSU 180 degrees.  Draw in warmer case air, exhaust out the back.

As far as PSU can't handle the heat load.  It will handle it just fine.  MOST PSU draw in warm case air.  Take a look at any rackmount server PSU.  They ALL draw in heated case air.  In a datacenter the power is likely 208V.  At 208V/240V PSU tend to be 1% to 2% higher efficiency.   At 90% efficiency you are looking at 50W heatload.   It is like the ultra difficult task of cooling a lightbulb in 90F air.   You know like what happens every single day outside in the summer. 

SeaSonics are built like a rock.  Open one up or look at reviews which show internals.  Massive heat sinks, giant transformers, oversized Japanese caps.  I ran a farm of GPU in a 90 deg garage for better part of two years using SeaSonics.  Not a single one died, not a single one underperformed.  We are talking 1200W units, 90F ambient,  dusty conditions, 95%+ load.  They just work.
2648  Economy / Computer hardware / Re: [WTB] Waterblock for Radeon HD 5970 on: October 19, 2013, 07:18:35 PM
Ok I'll take 2.  Grin 

Sounds good.  Will PM you.
2649  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 19, 2013, 07:16:00 PM
My point is that any delay in shipping also means a delay for MPP as it is currently tied to the delivery date of the Batch 1 unit. So if HF ships 4 weeks late, your MPP modules will also arrive 4 weeks later. That will significantly impact your ability to earn back your investment cost.

Having the MPP 'oasis' date being Nov 1 would be very fair, at least we would be able to count on the extra miniboards near feb 1.

Hashfast can we get an official word on this?  While not stated in the original MPP terms if shipment is delayed it would provide some partial assurance if that event doesn't also delay the MPP.  Can the company consider having the 90 day window for MPP begin 1 Nov regardless of actual unit shipment date (with computed return towards break even beginning based on actual shipment date).  Just one way HashFast can show they are the professional choice.
2650  Bitcoin / Hardware / Re: HashFast launches sales of the Baby Jet on: October 19, 2013, 07:11:05 PM
HashFast have the final PCB been produced?  If so can we see some photos?  
I am interested in final dimensions, locations of power connectors, etc.
2651  Other / Politics & Society / Re: Re: Bye bye bitcoin (Split: Morality of Bitcoin vs. Fiat Discussion) on: October 19, 2013, 12:34:24 AM
"The cause is because of legal tender laws that require fiat to be accepted by those giving out loans."

What exactly does this mean? That legal tender must be accepted (i.e, if I lent you 10 BTC, when they were worth $10 apiece, and now they're $100 apiece, so I must accept $1000 USD as my payment) or that loans must be denominated in legal tender? If its the latter, how does shorting work?

The former. I must (in the US or when lending to a US citizen) accept $1000 from someone owing me 10BTC when BTC is worth $100. That is retarded and any lender who exercises that right won't ever lend from me again (you can ask me whether I would accept it though).

An extension of this is that damages in a court of law are awarded in legal tender.

So someone borrows 100 BTC fails to repay and you sue them.  Assumming the court agrees that the debt is valid they will enter a judgement in legal tender so if the current exchange rate is $200 USD per BTC the court might award a judgement of $20,000.   You may collect the value of your damages but you have no guarantee it will be paid in anything other than legal tender.
2652  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 18, 2013, 10:38:12 PM
I do not want to buy 10, but maybe 1 or 2 sierras. How much does the 1U control unit cost ?
How much power consumption for the controller unit ? Has it 2 Ethernet ports, USB ports ?
edit: How will it be connected to the miners in order to control them ?

I don't believe HF is selling a control unit seperately the 1U control unit is simply a "free" upgrade if you buy 10 Sierras (nicely fills an entire rack).

The Sierras have a single USB port connection on the back.  Any system (capable of running cgminer) can be used as a host/controller.  There isn't anything particularly special about the "1U controller" it is simply an entry level 1U server.  You could buy your own "off the shelf".  Even an Atom server w/ 2GB of RAM likely more than enough computer "oomph" to run cgminer for as many modules as you want to connect.  If you have more Sierras than USB ports just use a USB hub.

Even if it isn't available for sale maybe HF can share the specs (processor, RAM, HDD, etc) for the controller to help customers find an equivalent.

Still I imagine the requirements are modest.  This is likely overkill.
http://www.newegg.com/Product/Product.aspx?Item=N82E16816101365
2653  Bitcoin / Hardware / Re: KnCMiner Jupiter Miner First Impressions on: October 18, 2013, 10:01:31 PM
1hr result with firmware v0.9.5
Not much different at this time.

Does v0.9.5 improve or worsen power consumption at the wall?
2654  Other / Politics & Society / Re: Re: Bye bye bitcoin (Split: Morality of Bitcoin vs. Fiat Discussion) on: October 18, 2013, 08:42:59 PM
Quote
There's a reason why the free market chose to practically abandon gold and silver.

It's not because of Gresham's law, though. Gresham's law only describes the symptoms, but not the cause. The cause is because of legal tender laws that require fiat to be accepted by those giving out loans. Of course bad money drives out good. But the money is still bad and being propped up as equal to the good money. Once it's no longer propped up in such a fashion, the reverse happens, and typically quickly.

This.  The often misquoted Gresham's if often misquoted to mean "bad money displaces good money" but this important caveat is UNDER GOVERNMENTAL FORCE.  As for spenders it makes sense.  I have this dollar I don't trust and I have this lump of gold I do trust.  I will save the gold and spend the dollar.   However if one thinks a little deeper if logically one wants to keep gold and get rid of dollars why would a merchant accept dollars.  Maybe they would in a limited fashion to quickly exchange the dollar for gold and pawn the risk on some other sucker but if everyone is doing that then essentially there is no market for the bad money.  However Gresham's law is pointing out that if the government makes the bad money legal tender and thus obligating its acceptance is certain scenarios then the better money is displaced.   Without the government using force people would simply demand the better money (gold) or at a minimum charge a higher price for payment in the bad money.
2655  Other / Politics & Society / Re: Re: Bye bye bitcoin (Split: Morality of Bitcoin vs. Fiat Discussion) on: October 18, 2013, 08:37:36 PM
Bitcoin is not a currency. It can best be compared to rare football game card collecting. It has no value except for the imaginary value assigned to it by a small flock of enthusiasts. (Of course there is an very interesting and new technology behind it, but that is a completely different story)


The same could be said of all current, future and past currencies the only difference is the size of the "flock of enthusiasts".
2656  Other / Off-topic / Re: What would be mining machines look like by 2037? on: October 18, 2013, 08:35:11 PM
bitcoin encryption decrypted and bitcoin worth 0 by then. DUH!  Wink   Roll Eyes

What encryption?
2657  Economy / Computer hardware / Re: [WTB] Waterblock for Radeon HD 5970 on: October 18, 2013, 08:30:49 PM
Was wonder if anybody had a spare waterblock for a 5970 lying around. I live in the United States.

I may still have a couple (unused in original package).  Danger Den brand.  I will take a look tomorrow morning.

It is this model (full body water block covers VRMs, GPU cores):
http://www.dangerden.com/store/dd-5970-water-block.html

Yup still have some left.  Never used, original in box.  DD made a batch of them specifically for me because no stores were stocking them at the time and I needed like 40 but their min order was 50 units so I have some left over.

I will post some  photos tonight if you want but it looks just like the store link above.  $60 for one plus actual S&H (first class or priority mail) or $100 for two w/ free shipping (priority mail).   Buy two and get a used 5970 for double the fun. 

Paid in BTC using bitstamp rate at time of payment.  Let me know.
2658  Bitcoin / Hardware / Re: HashFast announces specs for new ASIC: 400GH/s on: October 18, 2013, 07:32:48 PM
Also...they signed an agreement to buy off the shelf PSUs? Because i don't think they will design a CUSTOM PSU.

Contracting for a lower price by agreeing to a volume is pretty common in the business world.  Both sides win (and likely have compensation if agreement is not lived up to).  No need for a custom unit if stock units fill the need.

2659  Bitcoin / Hardware / Re: HashFast launches sales of the Baby Jet on: October 18, 2013, 06:39:41 PM
CoolIT has already developed dual processor liquid cooling system back in 2010 that can dissipate up to 900 watts of heat.  2 of them should be able to fit in the new 4U chassis.  With Overclock performance of over 500 GH per chips (according to Simon's post in the other thread) that is 2TH in a single box, same as Cointerra's TerraMiner IV...  Speaking of which, you can see Cointerra's new 3D renderings of their 4U case design and see they use 1 large radiator to cool 2 ASIC chips.   One can only dream!

One "issue" (only for a moder) with those preconfigured waterloops is generally they are sealed systems.  You can't add an extra waterblock.  So while the unit can handle 900W of heat you couldn't connect 3 waterblocks to it.  Still based on the dimensions it does look like HF could use two waterloops like that to cool 4 boards per chassis (call it a 4 module Sierra or maybe give it a new name).   Lots of interesting options.

I (maybe a minority) am more interested in a custom solution.  Single large radiator, separate pump, separate reservoir and the ability to custom built a different solution.  Using two "server" style power supplies (they tend to be thinner) one could maybe put 6 modules in a single chassis (4U).  Smiley
2660  Bitcoin / Hardware / Re: HashFast launches sales of the Baby Jet on: October 18, 2013, 02:36:39 PM
Thanks for all the technical details Simon it certainly clears up a lot of stuff.   I agree on the choice of PSU vendor.  Used SeaSonics to power a GPU farm and they worked flawlessly at high load in brutal conditions.

BTW any plans to sell just "naked boards"?
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