Topic: CoinCraft A1 28nm promises up to 2 TH/s at 0.35-1W/GH (Read 2717 times)

hi

what is the delivery date?

They have a winter sales discount of 20%, so the 2TH rig is now "only" $11.999!

 

Heat... you will need a superior cooling solution to get that 25%. Most of these 28nm designs no matter which you choose will need to take that into consideration. Here is hoping whatever chip you settle on that the package they use first works and it doesn't leave you waiting for revisions. There is plenty of pitfalls putting these chips on to PCBs that need to be considered in the package design.

That's exactly the game they're playing with their specs.  they quote the low power J/GH trick... without quoting the performance... and then somewhere else they quote the performance, but are not quoting it for the low power mode.   What you want is a categorical statement as to what performance it hits at what power consumption for each of the modes... and they've never supplied that!  Probably because they have no idea what the performance of it in low power mode will be.     And whatever performance it gets, so will everyone else.. because reducing the voltage on a chip isn't new.  its just not economic to do it, as everyone wants max performance, not min performance for their dollars!

Cooling four 300 W chips is kind of straight forward as they're in the ballpark of what high end enthusiast over-clocked intel chips clock at... thus theres a wealth of cooling technology that fits the bill, including the liquid cooling that cointerra (and hashfast) are using... and also, air based coolers with giant metal heatsinks like what KnC are using (Arctic A30).

Whats not clear is that if you need Forty 30 Watt chips to do what Four 300 W chips can do, to both yield 2 Terahash in a 4U box...   then its actually a much harder problem to cool 40 chips than 4...   as those 40 chips will still need something much better than regular air cooling.. and each chip may need its own heatsink.. or, one huuuuge heatsink that covers all 40 chips... etc etc..

Its probably easier to cool 4 hot chips because you definitely know where the heat is coming from and can use liquid to move it to the outside of the box...   whereas with 40 chips the heat is coming from everywhere, spread out.. and not easily contained.  You're relying on AIR to move it to outside of the box, which may actually be more difficult.  Liquid moves heat much more efficiently than air.

as you say, the proof of the pudding will be the cooling.   whose cooling solution works better is going to be the critical component of comparing these two designs... as well as cost.  so far, for january prices, cointerra's is half the price of bitmine's.  presumably for feb prices too, cointerra will be lower cost.

Having four big chips is probably cheaper to manufacture than having forty less big (but not small) chips.  its a bigger board, (actually, its a lot of boards, each with a bunch of chips on it.. 8 per board?) with more dc/dc converters, and more 'chip packages' and yet its the same total power consumption and total performance.   Whats worse, they're all daisy chained together!!   one fails, they all fail.  like the old fashioned christmas lights.

I just pulled that information from their tapeout announcement: https://bitmine.ch/?p=2049

Mostly though my point was that packing 300W into a single chip sounds to me like a major challenge, and IMO is not a good way to go about making a miner chip.

I guess the proof will be in the pudding.

Bogart,  thats not correct.  you are letting yourself be misled by bit mine's use of low, nominal and turbo power modes, and the ensuing confusion by cross quoting the performance along each of those modes.

https://bitmine.ch/?page_id=863

Bitmine have not stated the performance of their chip when undervolted ('low power' mode).   Did they really say it ran at 32 GH/s?  at 0.4 J/GH??   or did you just make that up?

Their spec (link above) says clearly 25 Gh/s at nominal 0.6 J/Gh.   And if they upped it to 32 GH, then its still at 0.6 J/GH and not 0.4 like you're stating.  We have asked them numerous times what the chip performance is when under-volted and they've never said the performance.  I'm guessing its half... i.e.: 15-20 GH/s at 0.4 J/GH.

Psst... all 28nm designs face a challenge. No matter what.

I'd put money on it.  Oh wait, I already did.

October 1, 2013: CoinCraft tapeout announcement: https://bitmine.ch/?p=2049

November 8, 2013: CoinTerra tapeout announcement: http://cointerra.com/cointerra-open-silicon-announce-tape-goldstrike1-asic/

I made my decision before either tapeout announcement, based on the chip designs.

CoinCraft chip: 32Ghps @ 0.4J/Gh nominal == 12.8W TDP

CoinTerra chip: 500Ghps @ 0.6J/Gh nominal == 300W TDP

It was clear to me which design faced fewer challenges.

Don't these hit before cointerra ?

They seem expensive pretty expensive compared to Cointerra's price for 2Th..

2TH is actually in this case 2.8TH and possible +25%
(2TH nominal speed, 2.8TH turbo mode and +25% as A1 chips seems perform possibly better than expected)
Im just wondering if chips hash +25 faster how PSU can handle this?!

https://bitmine.ch/?p=2226

Isn't the price way too high? or am I missing something? $12k for 2TH and january at best without a current working model?

Damnit... I suppose I should pull the trigger on ordering a January 2TH unit...

I was told the same as above.

My understanding:
Batch 1 orders are scheduled to ship on the "last week of December".  Batch 1 closed on 31 October 2013.
Batch 2 orders are scheduled for "January" delivery.

They're very real. Also not heard about any delay, I have two CoinCraft Desk orders confirmed some time ago to ship last week of Dec and few days ago got info by email that new orders (placed now) will ship mid Jan.

Where did anyone state they are delayed a month? Not read that.

I think they're delayed about a month? Others will confirm as I don't really follow CoinCraft.

What did they say about shipping time? On their website they state 'production starts late december'.

I have ordered (and paid for) a 2 TH/s Bitmine CoinCraft Rig (#CCR-2000).

Legit.

As with any 28nm there will be design issues. Follow the current threads they have up for more details.

They have shipped Avalon Clones previously. As with any of these companies do your own home work. Assess the answers you get from them directly and talk to people who deal with them or communicate directly with them if you can. Our group is going to invest a modest amount in A1 chips and try and produce our own miners. Again do not invest anymore than you are willing to lose.