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Topic: Hacking a BFL Single/25 to 48gh and beyond..... - page 3. (Read 8423 times)

legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
And in the meantime, it looks like I just bought a 100% BROKEN single. So now I'll have another thing to figure out and keep me busy...

C
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
To check the 1 volt, can't you check the resistance to ground of the 1 volt supply like you could on a Jally???
You know, I didn't think about that. If I could find the 3.3 volt test point I could also find that as well (3.3 is shared between sides). But I seem to recall a loaded jally has a very low resistance to ground. What would it be, probably under 1 ohm.

I'll do that.
newbie
Activity: 7
Merit: 0
To check the 1 volt, can't you check the resistance to ground of the 1 volt supply like you could on a Jally???
hero member
Activity: 650
Merit: 500
Pick and place? I need more coffee.
Look for a 7K resistor between two ASICs.  On the jalapeno it is R11. Not completely sure on the resistor with singles but the ASIC layout looks the same as a Jala.

I am going to mod one of my singles this week with a 7.5K resistor.  The one I am changing the resistor in only does about 57Ghs with stock firmware.  Hope this

puts it over 62Ghs.  Will post results. Grin

legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Gonna watch this closely.  I have a single that pulls 62Gh at about 64C.  Thinking about replacing the feedback resistor like I did in my jalas to put

about 1.1V into the ASICs.  Wondering if the mosfets can take this though. With the jalas is was a marked improvement with every one. +1Gh and
Ok, I'm ordering the resistors. 0603 size, 8.2k. Question: Do you know which resistors to do on the single board? I'm sure there is one per side, haven't tried tracing them out yet. The MOSFets on the Singles are more durable; they should handle it.

C
full member
Activity: 238
Merit: 100
"This is a stock BFL supply current limited"

Limited to Huh how many amps ? use automotive fuses 5 7 10 15 20 25, they are cheap start low on the feed lines. (newer plastic style with legs).
electronic fuses are available in fast blow, but harder to get.

Not sure how BFL does it, prolly a very fast sense digital circuit in the supply somewhere.

EDIT: Just thought about all the horror storys of the older BFL jally supplys Smiley so all bets are off on this one ....



legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Ok, here is an interesting question/problem:

Normally when I add chips to a jalapeno I plug it into the "danger supply". This is a stock BFL supply current limited so that if a chip is shorted the board will come up with a "beaconing" 12 volt LED instead of blowing the 1 volt supply to hell. It's worked well (this is how I found that old style chips can short internally) but with the single, there's a problem:

I can't fire the unit up on a jalapeno supply. And even an 8 chip jally will not boot with a jally supply, you need to use a big supply. Which means if you short, you're dead.

What can I do to protect the 1 volt supply lines as I add more chips? I'm confident that I can add factory chips, but I worry a bit that a reballed chip might have a slightly out of line ball. Normally not a problem, but if it shorts the 1 volt line....

Any thoughts?

C
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Ok, some pictures of this whole thing.

First, the board with 5 chips added to it, and the extra FETs and parts



Close up of the left-side FETs. Remember that the board sides are mirror images of each other.



Good shot of the board when I put on the first choke. Nice solid 1 volt.



And finally a shot of the other FETs and the driver chip during install.



Overall not bad, I'll put a sixth chip on it tomorrow or Tuesday based on how I feel.
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Ok. In the meantime all together, total of 5 chips on the right side, 8 on the left, both power supplies operational.

They way to test the power supplies for shorts or screw ups is to not install the choke, and check the voltage. If it's 2 volts or so the chip is good, if it's zero or something else you have a problem.

Once I put the choke on the overall voltage on the rail was a rock-solid 1.018 volts. Not bad, not bad.

The unit is now together and hashing at 48gh at 65c. Heat sinks are installed on the center FETs only since those get the least cooling. Oddly enough the stock fan was pointing *up* so I set the second fan to point up as well. I might try reversing it later, however I think the backwash of the fans going down will disrupt the cooling air going across the heat sinks (which it does nicely since the fins are parallel to the main air flow all around)

Edit: I changed it so the first fan points down, then the second up. Reason being I want the air to come in, be forced over the first heat sink, then zip up through the second sink, then out the unit. Keep the air flow smooth as possible, otherwise it bunches and your fan blades stall. Temps are 72c now, and quiet.

I'm still only feeding it with a single molex plug, part of the reason I am not going further on chips. The other reason is I am not feeling well today, so I'm done for the moment. Will post some pics as soon as I can find a USB cable for my phone.

C
hero member
Activity: 532
Merit: 500
The heat sinks are Enzotech's. Nice stuff actually, waiting for another batch to come in.

Right now working on adding chips 3 and 4 to the blind corners, will then add the FETs and go from there.

Edit: Chip 3 on and working, doing chip 4 and the six FETs. Wonder if it will read 1 volt even without choke 2 on there (ie: does the chip have a single point of reference for voltage sensing on the rail, probably)

C
Awesome, thanks, I got an 8-pack on order now Cheesy
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
The heat sinks are Enzotech's. Nice stuff actually, waiting for another batch to come in.

Right now working on adding chips 3 and 4 to the blind corners, will then add the FETs and go from there.

Edit: Chip 3 on and working, doing chip 4 and the six FETs. Wonder if it will read 1 volt even without choke 2 on there (ie: does the chip have a single point of reference for voltage sensing on the rail, probably)

C
legendary
Activity: 1484
Merit: 1004
bump to follow!  Cool
hero member
Activity: 532
Merit: 500
Well, that was a fun job. Microsummary: Ten chips on the board total, hashing at 35+gh, not bad. I really can do anything with anything and a Mouser catalog.

Quick details:

1) I don't have my darn heat sinks in, so I had to use some old small ones. Yuck.

2) I need to make a new back plate or something for this. I have the right heat sink, but it's balance on two chips right now, not great.

3) The 1 volt supply came up rock-solid. It must do the voltage sensing after the choke coil. Ok, makes sense.

4) Running one chip I heard a buzzing on the board. Added 5 12 volt caps on the right side. Added another chip buzzing still there. Turns out it was the POS BFL power supply buzzing probably because it's overloaded with 10 chips.

5) It really is working, maybe tomorrow I'll add the other six FETs to share the load. Which means removing that BFL heat sink on the left set of chips, not sure how to do that. Heat? Chisel? Putty knife?

6) Technically I have to remember that the 1 volt supply on the right here is handling the chip load with 1/2 of the FETs. So right now it's running equal to a 4 chip jalapeno.

7) I was too lame to put a fan on the second heat sink (it's the super-good one) so I just put a 120mm fan on the end blowing in. With the case on it should keep things reasonably cool, we'll see.

So now I have this thing running along with the Chili on one 500 watt supply. The other 500 watt is running an 8 chip, 2 7 chips, a five chip, and a four chip. Hm, it may be overloaded. Great...

Pics tomorrow, have a date tonight.

C
Sounds like you are having fun so far, nice accomplishment!  I do want to ask though... where do you get those square heatsinks you use on the back of the board?  I've had no luck finding any in my searches.  I also noticed you only put heatsinks on 1 of the 2 sets of FETs and on the ADP.  Any reasoning on that?
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Well, that was a fun job. Microsummary: Ten chips on the board total, hashing at 35+gh, not bad. I really can do anything with anything and a Mouser catalog.

Quick details:

1) I don't have my darn heat sinks in, so I had to use some old small ones. Yuck.

2) I need to make a new back plate or something for this. I have the right heat sink, but it's balance on two chips right now, not great.

3) The 1 volt supply came up rock-solid. It must do the voltage sensing after the choke coil. Ok, makes sense.

4) Running one chip I heard a buzzing on the board. Added 5 12 volt caps on the right side. Added another chip buzzing still there. Turns out it was the POS BFL power supply buzzing probably because it's overloaded with 10 chips.

5) It really is working, maybe tomorrow I'll add the other six FETs to share the load. Which means removing that BFL heat sink on the left set of chips, not sure how to do that. Heat? Chisel? Putty knife?

6) Technically I have to remember that the 1 volt supply on the right here is handling the chip load with 1/2 of the FETs. So right now it's running equal to a 4 chip jalapeno.

7) I was too lame to put a fan on the second heat sink (it's the super-good one) so I just put a 120mm fan on the end blowing in. With the case on it should keep things reasonably cool, we'll see.

So now I have this thing running along with the Chili on one 500 watt supply. The other 500 watt is running an 8 chip, 2 7 chips, a five chip, and a four chip. Hm, it may be overloaded. Great... Edit: Nope, it's pulling 470 watts from the wall which is fine. So you can run a max of 32 chips per 500 watt supply. I'll have to remember that.

Pics tomorrow, have a date tonight.

C
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Updates:

1) This is not easy :-)

2) Have the chip, 6 fets on, no choke, one capacitor on the 1 volt line. Note that oddly enough the 1 volt connections between the two sets of 8 chips are *NOT* connected. Note also that if you try to power with a 1a bench supply you will think you're dead. Man up and plug it into the big BFL supply. Either it works or it blows.

3) It seems to work. I see 2.5 volts at the choke inlet, remember choke is not on yet. Shorted the choke pads quickly and saw a nice solid 1.018 at the 1 volt test pad. Other 8 chips appear to come up on the other side.

Next step: Heat board, put on 5 more 1 volt capacitors, then try it out. I should get a solid 1 volt, in which case I'll check to see if I can put a chip on the board.

C
full member
Activity: 238
Merit: 100
Thank you for the Molex information. I think a stock corsair power supply will be able to handle 12 chips which is what I will go for this weekend; if it works I'll order some edge connectors and start moving to 16gh or so.

Speaking of which, I need another fan. Oh great, totally forgot that....

C

Fan : 120x120x25 is size Delta is brand gateway servers use em.

"Few" meaning three Smiley  leads on em...12v 4000rpm 45dba 130+ CFM 3wire

AFB1212SH
http://www.ebay.com/itm/Gateway-960-8006323-Delta-AFB1212SH-Back-Case-Chassis-Fan-30-Day-Warranty-/170822936596?pt=US_Computer_Case_Fans&hash=item27c5d72814

http://www.ebay.com/itm/Gateway-Delta-AFB1212SH-Back-Case-Chassis-Fan-/281046185168?pt=US_Server_Fans_Cooling_Systems&hash=item416fa874d0

http://www.ebay.com/itm/Delta-Elec-AFB0812SH-12V-DC-Brushless-Fan-/350343725894?pt=LH_DefaultDomain_0&hash=item51921d0346
legendary
Activity: 3164
Merit: 2258
I fix broken miners. And make holes in teeth :-)
Thank you for the Molex information. I think a stock corsair power supply will be able to handle 12 chips which is what I will go for this weekend; if it works I'll order some edge connectors and start moving to 16gh or so.

Speaking of which, I need another fan. Oh great, totally forgot that....

C
full member
Activity: 238
Merit: 100
Can't wait to see where this goes   Grin

Also watching Smiley

Adding info on PCIE headers plugs ect.
Before ordering make sure that the peg holes match a GPU connector. Been much confusion on that due to patent on PCIE Express by STB I believe it was. Aftermarket molex are called "something" JR.

http://www.frozencpu.com/cat/l3/g44/c155/s648/list/p1/DIYMod_Parts-Connectors_Pins-6-Pin_PCI-E_Connectors-Page1.html

https://bitcointalk.org/index.php?topic=379677.60

http://www.molex.com/molex/products/datasheet.jsp?part=active/0455590002_CRIMP_HOUSINGS.xml

finally to this:

http://www.molex.com/molex/products/datasheet.jsp?part=active/0455580003_PCB_HEADERS.xml
sr. member
Activity: 1316
Merit: 254
Sugars.zone | DatingFi - Earn for Posting
Can't wait to see where this goes   Grin
hero member
Activity: 650
Merit: 500
Pick and place? I need more coffee.
I don't think increasing the voltage increases the heat.  Increasing the voltage allows the firmware to bring up more engines at faster clock speeds

and this is what increases the workload on the FETs.  My theory anyway.  Before I did this to one of my 3 chip jalas I noticed that only

about 39 of the engines where online and most of the chips ran somewhere around 275Mhz.  After I installed the 8.2K resistor, All 48 engines

where running and the average clock speed was about 285.  This jala hashes at about 13.1Ghs with a temp of around 42C.  The FETs aren't sinked

and only feel warm to touch after 24Hrs hashing.  8.2K sets the DC-DC to around 1.08-1.1V.  Varies per board, all 8 of mine are a little different. Smiley


I do wish BFL had tied the 1V to some type of control logic that the firmware could control.  Maybe automatically increase it when conditions

are ideal or when errors are high.  Maybe even make it user adjustable but stipulate this voids your warranty.  Kind of like motherboards do with

cpu voltage.  I can see how a setting like this could be a self-destruct button for an uninformed user/owner.
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