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Topic: bASIC - speed boost - 54G now 72G, 27G now 36G (~) - page 2. (Read 3696 times)

legendary
Activity: 1274
Merit: 1004
The Seasonic rates the 8981 string to 7A because it's a fully modular PSU and those cables have a single pin of a 6pin Minifit Jr provide 12V to the whole string.

Ah, OK, so that's where the Seasonic's 7A limit comes from - I should have spotted that.

Quote
The problem isn't with the 8981; a non-modular PSU wouldn't have that issue.

Perhaps true for a premium quality non-modular PSU, but the ATX standard specifies 18AWG on the 8981 so you certainly can't rely on being able to draw 120W from the Molex on a low end PSU.

Good to know that there are PSUs out there that could power the bASIC directly from a peripheral connector - but notwithstanding that I think my point is still somewhat valid.  Many (most?) PSU's will not be able to power the bASIC and remain within spec without the use of custom cables.

I'm also wondering what the current draw of BFL is going to be.  If it's on the high side I may end up deciding to stay with the 13-14V wall wart to minimize the current through the barrel connector.

Right now it's true that we really have no hard information on power requirements for either product - and I imagine we may not for several weeks.  I guess all we can do is wait and see.

roy

You should be fine drawing 120W through the Molex connector even with 18 gauge wire. If your PSU is pretty standard with the first 4pin being about 1.5ft along the cable, you'll end up with a round trip resistance of a little under 15 milliohms for the single 12V and dual ground wires. You'd only lose 0.15V across the wire, which really isn't a concern. Wire heating should also not really be an issue unless your application is extreme.
hero member
Activity: 563
Merit: 500
The Seasonic rates the 8981 string to 7A because it's a fully modular PSU and those cables have a single pin of a 6pin Minifit Jr provide 12V to the whole string.

Ah, OK, so that's where the Seasonic's 7A limit comes from - I should have spotted that.

Quote
The problem isn't with the 8981; a non-modular PSU wouldn't have that issue.

Perhaps true for a premium quality non-modular PSU, but the ATX standard specifies 18AWG on the 8981 so you certainly can't rely on being able to draw 120W from the Molex on a low end PSU.

Good to know that there are PSUs out there that could power the bASIC directly from a peripheral connector - but notwithstanding that I think my point is still somewhat valid.  Many (most?) PSU's will not be able to power the bASIC and remain within spec without the use of custom cables.

I'm also wondering what the current draw of BFL is going to be.  If it's on the high side I may end up deciding to stay with the 13-14V wall wart to minimize the current through the barrel connector.

Right now it's true that we really have no hard information on power requirements for either product - and I imagine we may not for several weeks.  I guess all we can do is wait and see.

roy

staff
Activity: 4284
Merit: 8808
If both systems require the same variable, then they cancel each other out.

Only if you think profits and losses are the same thing.

E.g. one thing returns $10/mo, another option returns $5/mo. Now add a $6 cost to both sides.  Nor can you say that if one or the other was the winner ignoring the constant cost it would still be still be a winner with it as they don't have initial upfront costs.

Personally, for infinite duration things I like to convert constant future operating costs to unfront costs:  $10/mo in today's value forever costs you roughly $3000 (assuming 4% post-tax/inflation return).  Though mining isn't infinite duration and the long term trend of energy costs certainly seems to be upwards.
legendary
Activity: 952
Merit: 1000
You've forgot to consider at least 70W for the PC to control the ASICs (for both systems).
If both systems require the same variable, then they cancel each other out.

Side note, I'm hoping to cut that host PC down to < 5W. Maybe soon I can actually turn my computer off at night!
legendary
Activity: 938
Merit: 1000
   c. Consume 120 Watts (maximum estimate) ($7.78/mo @ .09c KWh)

Warning: Irrational exuberance detected.

Why the heck would you expect that a "maximum estimate" established for 3/4th of the hash power would still hold?


OK. Fine. I'll double the maximum power estimate to 240 watts (which I think is an outrageously high number). The bASIC is still on top.


You've forgot to consider at least 70W for the PC to control the ASICs (for both systems). On the other hand the 0.09c KWh is really low for most countries. In Europe range is 0.12-0.38 with most of the countries over 0.25c KWh. Considering the 0.25c KWh,  Basic lose over BFL over the 20X with $138/mo versus $139/mo. At 60X Basic will be barely profitable with $8.54/month.
legendary
Activity: 1484
Merit: 1026
In Cryptocoins I Trust
   c. Consume 120 Watts (maximum estimate) ($7.78/mo @ .09c KWh)

Warning: Irrational exuberance detected.

Why the heck would you expect that a "maximum estimate" established for 3/4th of the hash power would still hold?


OK. Fine. I'll double the maximum power estimate to 240 watts (which I think is an outrageously high number). The bASIC is still on top.

1. Buy from BFL (~$1300 invested)
    a. Get 60 Gh
    b. Get your ASICs in January/February
    c. Consume 60 Watts ($3.94/mo @ .09c KWh)
    d. Estimated profit at 10x difficulty: $327.52/mo
    e. Estimated profit at 20x difficulty: $161.79/mo
    f.  Estimated profit at 30x difficulty: $106.54 /mo
    g. Estimated profit at 40x difficulty: $78.92/mo
    h. Estimated profit at 50x difficulty: $62.35/mo
    i.  Estimated profit at 60x difficulty: $51.30/mo

2. Buy from Tom (~$1070 invested)
    a. Get 72 Gh
    b. Get your ASICs in January/February
    c. Consume 240 Watts (maximum estimate) ($15.56/mo @ .09c KWh)
    d. Estimated profit at 10x difficulty: $382.09/mo
    e. Estimated profit at 20x difficulty: $183.21/mo
     f. Estimated profit at 30x difficulty: $116.92 /mo
    g. Estimated profit at 40x difficulty: $83.77/mo
    h. Estimated profit at 50x difficulty: $71.66/mo
    i.  Estimated profit at 60x difficulty: $63.88/mo

EDIT: That "bASIC will use more than 120 watts" argument relates to the "BFL can't get 1Gh/watt argument", both of which no one really knows the answers to. It is doubtful any manufacturers have anything more than a prototype.
legendary
Activity: 1400
Merit: 1000
I owe my soul to the Bitcoin code...
Sounds like RAM Guy should stick with RAM then. While I don't rule out the possibility of the AX1200 using two pins on the modular connector for 12V, it would be unusual. Molex doesn't make any Minifit Jr connectors rated at 11A per pin as far as I know.

The AX1200 powers the entire 12V wire of a peripheral cable through a single mini-fit jr pin.

Personally, I planned for the worse: 120W power consumption. Given the poor choice of connectors on the bASIC, the only way to handle a 10 Amp @ 12V load with a modular PSU is to use a Y-cable. So I manufactured myself 10 of them. Each has a custom AX1200 modular connector on one end (populated with 4 mini-fit jr pins), and peripheral + power barrel connectors on the other ends. Both ends will be plugged in the bASIC. I built them out of 16 AWG and made them 4ft long, so they can handle 120W with only a ~165mV voltage drop.

The fact that Tom recommends a modular PSU (with no specially designed power cables) for the 72Gh/s bASIC means that either (1) he knows power consumption will be much less than 120W, or (2) he is as poorly prepared as all buyers and doesn't realize he will be driving the single mini-fit jr pin on the PSU's end over spec...

Do you think there will be any adverse effects of powering through both the 8981 and the barrel at the same time, of course without knowing how the pcb power circuitry is laid out yet?
staff
Activity: 4284
Merit: 8808
   c. Consume 120 Watts (maximum estimate) ($7.78/mo @ .09c KWh)

Warning: Irrational exuberance detected.

Why the heck would you expect that a "maximum estimate" established for 3/4th of the hash power would still hold?
mrb
legendary
Activity: 1512
Merit: 1028
Sounds like RAM Guy should stick with RAM then. While I don't rule out the possibility of the AX1200 using two pins on the modular connector for 12V, it would be unusual. Molex doesn't make any Minifit Jr connectors rated at 11A per pin as far as I know.

The AX1200 powers the entire 12V wire of a peripheral cable through a single mini-fit jr pin.

Personally, I planned for the worse: 120W power consumption or even higher. Given the poor choice of connectors on the bASIC, the only way to handle a 10 Amp @ 12V load with a modular PSU is to use a Y-cable. So I manufactured myself 10 of them. Each has a custom AX1200 modular connector on one end (populated with 4 mini-fit jr pins), and peripheral + power barrel connectors on the other ends. Both ends will be plugged in the bASIC. I built them out of 16 AWG and made them 4ft long, so they can handle 120W with only a ~165mV voltage drop, or even 168W with only a ~233mV drop.

The fact that Tom recommends a modular PSU (with no specially designed power cables) for the 72Gh/s bASIC means that either (1) he knows power consumption will be much less than 120W, or (2) he is as poorly prepared as all buyers and doesn't realize he will be driving the single mini-fit jr pin on the PSU's end over spec...
full member
Activity: 157
Merit: 103
This lack of info on power delivery among other things is making it challenging to plan for power delivery/equipment (let alone running purchasing roi numbers). Anyone know when we are supposed to get the info?
legendary
Activity: 1400
Merit: 1000
I owe my soul to the Bitcoin code...
The molex 8981 connector standard is 11amp max current, not sure why Seasonic would limit it to 4A under that, nor if that is the standard, but I would suspect not.

The Seasonic rates the 8981 string to 7A because it's a fully modular PSU and those cables have a single pin of a 6pin Minifit Jr provide 12V to the whole string. The problem isn't with the 8981; a non-modular PSU wouldn't have that issue.

The AX1200 is a fully modular PSU as well.
Sounds like RAM Guy should stick with RAM then. While I don't rule out the possibility of the AX1200 using two pins on the modular connector for 12V, it would be unusual. Molex doesn't make any Minifit Jr connectors rated at 11A per pin as far as I know.

Not that I've seen as well.
legendary
Activity: 1274
Merit: 1004
The molex 8981 connector standard is 11amp max current, not sure why Seasonic would limit it to 4A under that, nor if that is the standard, but I would suspect not.

The Seasonic rates the 8981 string to 7A because it's a fully modular PSU and those cables have a single pin of a 6pin Minifit Jr provide 12V to the whole string. The problem isn't with the 8981; a non-modular PSU wouldn't have that issue.

The AX1200 is a fully modular PSU as well.
Sounds like RAM Guy should stick with RAM then. While I don't rule out the possibility of the AX1200 using two pins on the modular connector for 12V, it would be unusual. Molex doesn't make any Minifit Jr connectors rated at 11A per pin as far as I know.
hero member
Activity: 602
Merit: 500
The molex 8981 connector standard is 11amp max current, not sure why Seasonic would limit it to 4A under that, nor if that is the standard, but I would suspect not.

The Seasonic rates the 8981 string to 7A because it's a fully modular PSU and those cables have a single pin of a 6pin Minifit Jr provide 12V to the whole string. The problem isn't with the 8981; a non-modular PSU wouldn't have that issue.

The AX1200 is a fully modular PSU as well.
legendary
Activity: 1274
Merit: 1004
The molex 8981 connector standard is 11amp max current, not sure why Seasonic would limit it to 4A under that, nor if that is the standard, but I would suspect not.

The Seasonic rates the 8981 string to 7A because it's a fully modular PSU and those cables have a single pin of a 6pin Minifit Jr provide 12V to the whole string. The problem isn't with the 8981; a non-modular PSU wouldn't have that issue.
hero member
Activity: 602
Merit: 500
The molex 8981 connector standard is 11amp max current, not sure why Seasonic would limit it to 4A under that, nor if that is the standard, but I would suspect not.

EDIT: One product, the Corsair AX1200 has had techsupport answer 11A for their peripherals:

http://forum.corsair.com/v3/showthread.php?t=100140

TBFT (to be fair though), I'm not in love with either molex or PCIE for power.
legendary
Activity: 1400
Merit: 1000
I owe my soul to the Bitcoin code...
At this point I am holding my breath until Tuesday to see what Tom's engineers are up to. Depending on the power draw of the device a multi-12v line cable may be needed. <--this is just speculation by the way.

Once I have some solid numbers I can hopefully devise something elegant. Smiley
full member
Activity: 154
Merit: 100
If not, there are tons of connectors out there - one in particular I can think off of the top of my head that I've put 100 amps through on a regular basis at very low resistance that one could replace the stock connector with if he felt uneasy about the one that was included.

Granted you shouldn't have to re-engineer something you spent your cash on, but if this is the least of my concerns - I'd be a happy camper!
legendary
Activity: 2212
Merit: 1001
Hey Cablez,bASIC's guys have a question & need your help!!!!!

Posted by Roy Badami :

"I'm rather worried about this.  80-120W @ 12V is 6.7-10A.   steve contacted Seasonics in another thread and we know that Seasonic PSUs can only supply a maximum of 7A on their peripheral (8981) connectors - i.e. what's commonly called a Molex connector.  That's only 84W @ 12V.  Other PSUs are unlikely to be any better.  So we seem to have a situation where it will quite likely be impossible to safely power the bASIC from the Molex connector on even a premium quality ATX PSU, but will instead require a custom cable to connect the Molex connector on the bASIC to a PSU connector with multiple 12V rails pins, such as a PCI-E connector or CPU connector.  

This seems far from ideal - I think we really need the bASIC to have a connector with multiple 12V rails pins, such as PCI-E.  I'm not sure how easy it will be to source 10A barrel connectors, either.  Josh has said that BFL have been having difficulty sourcing high current barrel connectors [ETA: and Cablez has likewise said he's had difficulty finding barrel connectors rated at 10A] although given BFL's lower (stated) power specs, and the fact that they seem to be planning to go with 13-14V for their wall warts, connector power draw is probably less of an issue for them.

I'd really like to be sure that the bASIC will come with a connector that is safe to run at 10A for extended periods of time without running so hot that it melts or otherwise creates a safety hazzard. Some clarification on this would be most welcome.  The Molex solultion works fine on the MMQ because it only consumes 40W - which is a current draw of just 3.3A.  I just don't see how it's going to safely work for a miner that's going to consume 2-3 times the power. [ETA: unless you use two of them, of course]"

https://www.btcfpga.com/forum/index.php?topic=104.30

Show'em what you got dude!!!!!!!!!!!!!  Wink

Edit:Here's what we ALL can use  Wink

https://bitcointalksearch.org/topic/wts-atx-psu-to-25-or-2155mm-12v-coaxial-plug-power-cables-new-product-74397
legendary
Activity: 1484
Merit: 1026
In Cryptocoins I Trust
 Shocked Shocked Shocked

1. Buy from BFL (~$1300 invested)
    a. Get 60 Gh
    b. Get your ASICs in January/February
    c. Consume 60 Watts ($3.94/mo @ .09c KWh)
    d. Estimated profit at 10x difficulty: $327.52/mo
    e. Estimated profit at 20x difficulty: $161.79/mo
    f.  Estimated profit at 30x difficulty: $106.54 /mo
    g. Estimated profit at 40x difficulty: $78.92/mo
    h. Estimated profit at 50x difficulty: $62.35/mo
    i.  Estimated profit at 60x difficulty: $51.30/mo

2. Buy from Tom (~$1070 invested)
    a. Get 72 Gh
    b. Get your ASICs in January/February
    c. Consume 120 Watts (maximum estimate) ($7.78/mo @ .09c KWh)
    d. Estimated profit at 10x difficulty: $389.87/mo
    e. Estimated profit at 20x difficulty: $190.99/mo
     f. Estimated profit at 30x difficulty: $124.70 /mo
    g. Estimated profit at 40x difficulty: $91.55/mo
    h. Estimated profit at 50x difficulty: $71.66/mo
    i.  Estimated profit at 60x difficulty: $58.40/mo

So... if you have decent power rates, you can invest $230 less and still make more money by buying with Tom (aslong as you have an old PSU lying around.) Yes, eventually when difficulty sky rockets the BFL unit will still be profitable when the bASIC unit will not be, but I have a feeling 2nd generation ASICs will be out before that happens and everyone will trade in their old units anyways.

EDIT: deleted creepy storage wars meme Smiley
sr. member
Activity: 364
Merit: 250
A result of hardware changes made.

Quote
bASIC
It is for this reason that we are going to grow our hashing cluster to 8 ASICs.  With two clusters on the larger unit, it will conservatively produce 72GH/s.  Yes, this is very good news - a 33% increase in hashing power!  Yes, this means the 27G unit now becomes a 36G unit.  These initial numbers are conservative estimates, but we expect that firmware and software updates will be able to iteratively increase hashing power as well.

Source: https://www.btcfpga.com/forum/index.php?topic=104.0

EDIT: Found another thread on this in wrong forum / https://bitcointalk.org/index.php?topic=127490.0;all
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