Topic: 1GH/s, 20w, $700 (was $500) — Butterflylabs, is it for real? (Part 2) - page 56. (Read 146909 times)

I don't think you can find a high efficiency switching power supply that isn't 120V-240V so that isn't an issue.  The issue would be access.  In most US homes other than dryer & range there are no 240V connections.  The other "interesting" thing is nobody makes 2500W powersupplies (due to lack of need and lack of access).  Even w/ a pair of PSU it is hard to get 2500W.  You could use a pair of 1350W but if your DC load is say 2300W (2500W AC at 92% efficiency) you would be loading a pair of 1350W PSU to 85%.  Ouch.  Generally not a good idea to push them beyond 75% for long term usage (and efficiency).  Maybe a pair of 1500W PSU?  Still 1500W PSU are 240V only because no UL rated device can be >1440W continual unless it has a 20A plug.

So maybe the device can only work @ 240V using a pair of 1500W PSU?  Just pointing out the wattage is "interesting".  You are right they may be highballing it however the MH/W is roughly 2x the single which would indicate they either found a chip twice as efficient or they aren't highballing it.

As any dedicated miner with more than a few Ghash/s ought to know, using a 240V circuit is a bit more efficient than using an equivalent 120V circuit - On the order of several percent difference. I should hope that this device would be capable of plugging into a high voltage circuit, if only for the efficiency improvement and not even the higher available amperage. (Think stove/oven/dryer outlet). Also, my gut feeling is that this wattage rating is slightly overstated (remember it was changed once already), to avoid another specifications mishap like what happened to the Single.

I agree that GPUs are "non optimal" due to their spacing but to say "fairly easy" is kinda an underestimation.  If you doubt it, go to Walmart pick up a 2500W space heater put it in a 4U case and make sure you keep the surface temp of the heater below 75C (yeah FPGA are rated for 85C but the die is a poor thermal conductor so if heatsink reaches 75C+ likely the internal temp of the die is way beyond safe limit).  Remember the rig box has 32 boards so the spacing between boards can't be that much.  

While the rigbox may be designed for datacenters before accepting pre-orders one would think it would be a good idea to caution potential customers.

Something like:
Requires 20A 120V or 240V dedicated circuit.  Warning: Will not function on 15A residential branch circuit.

I have no knowledge of the rigboxes, but I think the intended application is for datacenters, not homes.  Most DCs are wired for both 120 and 240v, as well as higher amp circuits.

As far as cooling, it's not so much like a box of 5970's in so far as the cooling design should be far, far superior to the GPUs.  The GPUs are about the worst cooling design you can possibly make and still be functional, mostly due to form factor constraints.  The two factors that make the 5970 so poor in terms of cooling (and why you can't put 8 in a box) is GPU2 ejects it's heat directly over GPU1 so it can make it out the back of the box.  This was "solved" by ejecting heat both forwards and backwards in the 6990, but at the expense of ejecting all that heat into the case... where it was sucked right back up in the fan and sent back over both GPUs. 

Then there'st he fact that these vertical cards, ejecting heat everywhere are sandwiched together to fit in a PCIe slot, giving zero airflow.  If you aren't constrained by either design requirement, you can cool 2500w in a 4U case fairly easily, assuming you have proper airflow.

Those are good points.  Imagine how hot a 4x 5970 open air rig gets (~1200W).  Now put it in an enclosure (even w/ massive fan airflow) and watch the temps soar.  Now double the output.  That would be the heat output of a rigbox.  8x 5970 in a single enclosure.

The electrical issue is also "interesting".  US electrical code requires a 20% derate for continuous usage appliances.  So 120V * 15A * 0.8 = 1440W.  This is why you see no power supplies >1400W in US markets.  Any company selling a product pulling >1400W faces liability issues.  A 20A circuit (1920W) would be sufficient but many homes lack those except in the kitchen.

I don't think the wattage is a problem in markets where 240V is common.  If it was anyone else developing this product we likely would get some details/insight/explanations but BFL won't so it will remain a mystery.

Somebody pre-ordered back in early October.  No units have shipped. It isn't a lack of orders that is keeping the public from seeing a unit in the field. It likely will be some time (4-6 weeks ? ) before the first buyers get a unit and you are at the end of the list of unfulfilled orders.


I don't think you are going to get "scammed" in the traditional sense of someone runs away with the money.  I just think it likely will be Febuary or maybe March before you see any unit and the units may not live up to the standard/price you expect.  The company hasn't even given/lent a unit to Inaba to conduct long term testing.  Given the weeks/months long delays that doesn't seem to be such a hard thing to accomplish.


That makes sense.  Electricity is highly variable in price.  Revenue of any commodity is set by lowest cost producers.  It would make the most sense for higher cost producers to switch first.   The good news (for me at least) is that you anecdotal confirms something I have long suspected.  Most FPGA buyers will be doing so because GPU mining is no longer profitable thus they are replacing GPU for FPGA which should result in flat or lower aggregate hashing power.  If that tends to be true for most buyers that means GPU will "last" longer in lower electrical cost environments.

Subbing to the new thread.  Mostly interested to see how the big rig turns out.

Thank you for stepping up like this and keeping us in touch. Just what we needed right now !

True enough, and I'll definitely keep everyone well informed.

FWIW, I don't think you are an idiot. You've obviously weighed your options and have reached a valid conclusion for your situation. I would be very interested to follow your test case. Please keep us informed. I believe gigasvps has also posted that he has placed an order and would let us know his experiences. Haven't heard from him since, though, but honestly I doubt there will be anything to report until BFL actually starts shipping.

Done.

Order Confirmation:

Thank you. You will receive payment information in the next 24 hours. Once payment is received, your order will be secured.

Delivery will follow in 4-6 weeks. To check the status of your order, email us anytime at [email protected].

We appreciate your business and we hope you are as excited about your purchase as we are to offer you this product.

Kind regards, Butterfly Labs Inc.

Gents, I'm going to fall on my sword I think and order a couple of these.   Not sure if anyone else here has a standing order, but regardless you can use me as a test case to follow from preorder, to delivery, to product testing.

Save your posts about me being an idiot, and wasting my money, and being scammed.   I'm a big boy and willing to take the risk.   If anything, this means you don't have to and can simply follow my progress for better or worse.

My thinking Behring purchasing these is fairly simple.   At the moment I have 4×5870s mining away and have had for a fair while now.   I live in Australia so unfortunately its now our summer. The next 4 days alone are going to be 32, 36, 38 and 35 degrees C, and my cards are already contemplating suicide.    The heat, noise, wear and tear (one card has already lost its fan and needs to be RMA'd) and general pain in the arse of GPUs is already enough for me to consider other options, and then there's the power bill.   Electricity is not cheap here and its already wiping out a lot of my profits.  This is my main reason for doing this.

I don't game on my PC (I have consoles for that), so I'll be able to sell all of my GPUs to offset at least half the cost of this endeavour.   Yes it'll take a while to pay off the rest of the cost just by mining, but at least I won't have to factor power costs into that as well, at least not to the extent I do right now.

I've spoken to Sonny via email and asked the questions I needed to know before proceeding, and I'm pretty much ready to jump on board and take the risk.

Again, you no doubt think I'm an idiot, but that's not your problem, and I don't need to hear it.  I'll post again once I've ordered.

It would be interesting to know how BFL plans to power that Rig Box. In North America, the lowly standard 120V electrical outlet is limited to 15 amps. 1800W hair dryer yes, 2500W Rig Box no. Cooling such a small enclosed box would be challenging as well ... 2500W happens to be the heat generated by a stove element on High. 2500W also happens to be the heat generated by 10 PC's with their quad-core CPU's on full load, all crammed into that tiny enclosure. How effectively can something like that be cooled?

Have to say, despite all the shit slinging, I'm interested. Maybe even for the big rig... if THOSE numbers are even close to accurate ($25,000 50.4GH/s 2.5KW) then it'll pay for itself in under 6 months (earning over half my salary!).

Pipe dream though, prolly just buy two of the singles

The word from them to me currently is:
Perhaps Bensoutlet will finally deliver my 5870's around the same timeframe  

Oh, it is. It's just that there was a lot of talk about a mid-January delivery.

Luckily, they are keeping their customers apprised...

Guys, what's the word from BFL?

Oh.  I thought that was still in "4-6 weeks".

You know...the one where their much anticipated product ships to consumers...

What big day?

two weeks until the big day! bring it, bfl.