Klondike - 16 chip ASIC Open Source Board - Preliminary

[joeventura]

Unfortunately when I started the design I hadn't heard anything about over clocking Avalons and didn't design that in. I added some head room on the power supply just out of safety. I'm not aware of any higher current easy to swap regulator solution so the 3 options I see are:

1. Just place 14 chips / board. The wasted 2 chip board space isn't much of a loss.

2. Scrub the extra power connector behind the PCIe and add a IR3897 9A reg there to supply 4 of the end chips. This would cost a bit extra for parts - rough guess, about $5 maybe.

3. As #2 but extend the board by about 2cm and add 4 more chips, plus a full 16A IR3895 reg behind the PCIe conn. This would supply 6 chips, with 2 of those taken from current 16, making a 20 chip board. This would cost only a bit more than #2 due to higher board cost and the parts being a bit more costly, rough guess, about $8 maybe, but a more radical design change due to heat sink size also being different.

Another data point - the IR3895 over current protection kicks in at 18A minimum, so how well it behaves at max load probably depends a lot on how well it's cooled. Also, some of the reported power use in the other thread is for control board, 3.3V supply and fans so it could be somewhat less for actual ASIC power.

What would be the (estimated) hash rate of those 3 options?
I think Option #3 is probably too radical especially if folks like Terrahash have cases being built

[nightyj]

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

[loshia]

Unfortunately when I started the design I hadn't heard anything about over clocking Avalons and didn't design that in. I added some head room on the power supply just out of safety. I'm not aware of any higher current easy to swap regulator solution so the 3 options I see are:

1. Just place 14 chips / board. The wasted 2 chip board space isn't much of a loss.

2. Scrub the extra power connector behind the PCIe and add a IR3897 9A reg there to supply 4 of the end chips. This would cost a bit extra for parts - rough guess, about $5 maybe.

3. As #2 but extend the board by about 2cm and add 4 more chips, plus a full 16A IR3895 reg behind the PCIe conn. This would supply 6 chips, with 2 of those taken from current 16, making a 20 chip board. This would cost only a bit more than #2 due to higher board cost and the parts being a bit more costly, rough guess, about $8 maybe, but a more radical design change due to heat sink size also being different.

Another data point - the IR3895 over current protection kicks in at 18A minimum, so how well it behaves at max load probably depends a lot on how well it's cooled. Also, some of the reported power use in the other thread is for control board, 3.3V supply and fans so it could be somewhat less for actual ASIC power. Same performance with 14 clocked chips like 16 not clocked. And you save two chips and the end

What would be the (estimated) hash rate of those 3 options?
I think Option #3 is probably too radical especially if folks like Terrahash have cases being built

Depends how much are you gonna to overclock them.

In general with 14 chips you are loosing 2 chips = 13% of the hash power (300 clock), but you gain 15% with overclocking to 350 per chip which is at + for me

[loshia]

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

You are damn right about it. But it costs money for sure. The goal is to make it work in a stable way and to minimize the cost. this is just a compromise that we have to make and reach our sweet spot

[marto74]

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

+1
But first let's make it hash

[Igor_Rast]

+1 for Adding additional voltage regulators for stable work and spreading the load to let them all run at a lower current , better for the heat ( life)

but 12x12 idd disagree . The 10x10 was one of the first design rules that were used, changing that may have consequense on allot of folks (terrahash and other DIY guys) already prepping up  . But I would think nobody wil want to let 2 chips do nothing

terrahash will have a hard time figuring out what they wil have to do with these 2 chips , Offer all the people a upgrade to add 4 more chips , or refund or some kind that nobody wil want

10x10cm PCB and 16 chips that was golden . Nobody said how many regulators it will be having

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

[bigbeninlondon]

+1 for Adding additional voltage regulators for stable work and spreading the load to let them all run at a lower current , better for the heat ( life)

but 12x12 idd disagree . The 10x10 was one of the first design rules that were used, changing that may have consequense on allot of folks (terrahash and other DIY guys) already prepping up  . But I would think nobody wil want to let 2 chips do nothing

terrahash will have a hard time figuring out what they wil have to do with these 2 chips , Offer all the people a upgrade to add 4 more chips , or refund or some kind that nobody wil want

10x10cm PCB and 16 chips that was golden . Nobody said how many regulators it will be having

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

Above in bold; I remember the discussion where BKKCoins explicitly stated that the design wasn't ready before releasing it.  Anyone who ramped up on that design was warned ahead of time.  I personally don't think this should really have any weight in BKKCoin's decision making process.

[loshia]

---------------
2. Scrub the extra power connector behind the PCIe and add a IR3897 9A reg there to supply 4 of the end chips. This would cost a bit extra for parts - rough guess, about $5 maybe.
--------------

+1,

4 chips x 2A = 8A and we will drive IR3897 at 88% load. Can we just solve one problem and create another? Do we need powerful reg? 10 Amps  at least?

[Igor_Rast]

+1 for Adding additional voltage regulators for stable work and spreading the load to let them all run at a lower current , better for the heat ( life)

but 12x12 idd disagree . The 10x10 was one of the first design rules that were used, changing that may have consequense on allot of folks (terrahash and other DIY guys) already prepping up  . But I would think nobody wil want to let 2 chips do nothing

terrahash will have a hard time figuring out what they wil have to do with these 2 chips , Offer all the people a upgrade to add 4 more chips , or refund or some kind that nobody wil want

10x10cm PCB and 16 chips that was golden . Nobody said how many regulators it will be having

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

Above in bold; I remember the discussion where BKKCoins explicitly stated that the design wasn't ready before releasing it.  Anyone who ramped up on that design was warned ahead of time.  I personally don't think this should really have any weight in BKKCoin's decision making process.

Thats also true .   but some added parts on the pcb could work better then resizing , if you want to keep 16chips then . All up to BKK indeed
there is that opensource avalon clone too , 10 chips in 2 rows , maybe there its not that big of a problem

[fasmax]

+1 for Adding additional voltage regulators for stable work and spreading the load to let them all run at a lower current , better for the heat ( life)

but 12x12 idd disagree . The 10x10 was one of the first design rules that were used, changing that may have consequense on allot of folks (terrahash and other DIY guys) already prepping up  . But I would think nobody wil want to let 2 chips do nothing

terrahash will have a hard time figuring out what they wil have to do with these 2 chips , Offer all the people a upgrade to add 4 more chips , or refund or some kind that nobody wil want

10x10cm PCB and 16 chips that was golden . Nobody said how many regulators it will be having

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

I am not sure if TerraHash would really have a hard time figuring out what to do with extra ASIC's didn't they sale by hash rate? If they could achieve the rated hash rate by only placing 14 chips would this be a problem for them?

It seems adding regulators at this point could delay the release of the finished product.

At this point in time is seems like BkkCoins best use of time would be to finish testing the current design.

Just my thoughts.

[nightyj]

---------------
2. Scrub the extra power connector behind the PCIe and add a IR3897 9A reg there to supply 4 of the end chips. This would cost a bit extra for parts - rough guess, about $5 maybe.
--------------

+1,

4 chips x 2A = 8A and we will drive IR3897 at 88% load. Can we just solve one problem and create another? Do we need powerful reg?


BKK please consider adding the appropriate reg later on.

10X

88% of load is too much, personally I will not load voltage regulator with more than 70%, ye we all think of the lower cost, lower space but adding some regulators for 10$ more will help a lot in safety and reliability, this change will increase price of the product with arround 5% which is funny.

[GandalfG]

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

More efficient voltage regulators and cooling are best way in my opinion. Don't change board size.

[loshia]

88% of load is too much, personally I will not load voltage regulator with more than 70%, ye we all think of the lower cost, lower space but adding some regulators for 10$ more will help a lot in safety and reliability, this change will increase price of the product with arround 5% which is funny.

+1
But let us leave regs for now. When BKK reach the "first share point" and have the board hashing he can easily measure the chip consumption itself at 350 and share the result. Above 350 is not needed as long AS avalons are not performing and producing a lot of crap HW errors. then we can move on with that discussion. If board stay unchanged in terms of power design i will just remove 2 or 4 chips and that is all. if i do have 12 chips the planned regs will be driven at 75% max.

[marto74]

And you'll order 1 additional board per 6 planed now .
This is a good thing for us assemblers .
I'm joking , of course

[Igor_Rast]

+1 for Adding additional voltage regulators for stable work and spreading the load to let them all run at a lower current , better for the heat ( life)

but 12x12 idd disagree . The 10x10 was one of the first design rules that were used, changing that may have consequense on allot of folks (terrahash and other DIY guys) already prepping up  . But I would think nobody wil want to let 2 chips do nothing

terrahash will have a hard time figuring out what they wil have to do with these 2 chips , Offer all the people a upgrade to add 4 more chips , or refund or some kind that nobody wil want

10x10cm PCB and 16 chips that was golden . Nobody said how many regulators it will be having

Adding additional voltage regulators will help not only for the overclock but for more stable work, lower noise psu, lower temperatures, if you make board 12X12 this will help also about cooling, cause the most produced fans are with this size, now stocking a quallity 10cm fan is hard.

I am not sure if TerraHash would really have a hard time figuring out what to do with extra ASIC's didn't they sale by hash rate? If they could achieve the rated hash rate by only placing 14 chips would this be a problem for them?

It seems adding regulators at this point could delay the release of the finished product.

At this point in time is seems like BkkCoins best use of time would be to finish testing the current design.

Just my thoughts.

4.5 GHash/sec Board (has 16 chips) quoted from there site .
 So yes should have 16 asci chips. as for the people that bought chips themself , mostly did it in 16chips steps

Overclocking thats another thing , having risks on its own , the 4.5 G/Hs was stated when the Avalon specs were release stating 282mh per chip so 4.5 G/H


Quote from the Klondike Github
This is an open source effort to design and build a Bitcoin mining board based on the Avalon ASIC. The final goal is to have a small 10cm x 10cm board that holds 16 ASIC chips.

So the extra reg needed to overclock is like an extra . Think everybody will agree to pay just a bit extra for the parts if needed , its better that then to loose 50mh per chip

Or just trace them on the PCB , and only the overclocking guy would populate it himself ( bridge a connection to make it work ) , so all the cost stay the same. just an idea

[mike2kt]

Unfortunately when I started the design I hadn't heard anything about over clocking Avalons and didn't design that in. I added some head room on the power supply just out of safety. I'm not aware of any higher current easy to swap regulator solution so the 3 options I see are:

...

Hold that thought! IRQ announced the IR3847 SupIRBuck 25A back in March. Its pin-out is slightly different from theIR3895, but still in the PQFN 5x6mm package. Like the theIR3895, the IR3847 does not require a heatsink at its rated capacity.

Though there are two disadvantages. First it’s 25 to 50% more expensive than the IR3895 (no big surprise). The second issue is more pertinent - the availability of the IR3847.

http://www.irf.com/product-info/datasheets/data/ir3847m.pdf

http://www.mouser.com/ProductDetail/International-Rectifier/IR3847MTRPBF/?qs=%2fha2pyFaduh%2fXEfQX9qpOqsExJAQZ85xEuH%2ffjP3Ys6cnVXvB1KVwg%3d%3d

[loshia]

And you'll order 1 additional board per 6 planed now .
This is a good thing for us assemblers .
I'm joking , of course

true marto unfortunately you are correct

[Vigil]

I am an engineer with a background in aerodynamics/fluids and am capable of performing Heat/CFD simulations. Is there any way I can contribute to the heat sink/dissipation design. I can't promise anything but I can try if I had more understanding of what the goals/design are.

[USMCGrunt0307]

I am an engineer with a background in aerodynamics/fluids and am capable of performing Heat/CFD simulations. Is there any way I can contribute to the heat sink/dissipation design. I can't promise anything but I can try if I had more understanding of what the goals/design are.

Goal:  Keep shit cool, lol.  Im sure you could grab the component measurements off the net or make a rough estimate based on the PCB pictures shown in the thread and make a rough, scalable design.

[Vigil]

I am an engineer with a background in aerodynamics/fluids and am capable of performing Heat/CFD simulations. Is there any way I can contribute to the heat sink/dissipation design. I can't promise anything but I can try if I had more understanding of what the goals/design are.

Goal:  Keep shit cool, lol.  Im sure you could grab the component measurements off the net or make a rough estimate based on the PCB pictures shown in the thread and make a rough, scalable design.

I need to know how cool. I need estimates of heat generation of the chips (at least) and possibly the other components on the board. Fan or no fan? Stock components or custom (for the heat sink)? etc.