Bitcoin Forum
June 19, 2024, 09:55:36 PM *
News: Voting for pizza day contest
 
  Home Help Search Login Register More  
  Show Posts
Pages: « 1 ... 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 [108] 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 ... 405 »
2141  Economy / Trading Discussion / Re: Real Estate for Bitcoins on: January 15, 2013, 08:30:20 AM
Just curious, about how many BTC were you thinking of selling it for?

Well, it would be tied to a USD amount. Probably somewhere around $60k. So about 4500 BTC at the current rate.

Auto-goxlast-calc:
~
Getting cheaper every day..!
2142  Bitcoin / Hardware / Re: ASIC vendor status on: January 15, 2013, 05:55:06 AM
@SgtSpike I hope so. I have been a proponent of BFL for over 4 months and after a few delays I chose to end it. I could be wrong.

I have a feeling like my last post I read that as of Feb 11 there will be another update that will be less then acceptable.
Certainly, people will be getting very impatient if there is another delay on top of this!
2143  Bitcoin / Hardware / Re: ASIC vendor status on: January 15, 2013, 04:55:51 AM
I gave them an option to keep my order if they gave me a confirmed (by email) ship date which they chose to refund me (which I could have charged back). they chose to refund me then and there.

Then 2 days later after the bASIC implosion they offer an update with a firm date? OR is it? That is what you need to question. I could have saved myself a great deal of time and not bothered to post any of this info.

Unfortunately I am not a sociopath and I feel for other. I detest liars and CON-men. I hate seeing good people taken for A ride.

Have I mentioned I am a mechanic by profession and I have seen first hand how people get taken.

I'm just doing my part as a fellow red blooded human being. 
Right - like I told you before, they didn't want to make that announcement 2 days earlier than they did.  If they had told you a firm date, they would have done so knowing full well that such information would be spread around.  So, they had a choice - announce a firm date prior to when they really wanted to, or lose a couple grand on a preorder.

I guess I don't see a big deal from my perspective.  I don't see anything suspicious about them giving a refund to someone who asks for one.  Right now, they'd rather just keep everyone happy, and that probably means giving refunds as quickly as possible after they are requested.  They're not going to mess around with trying to give you dates when they don't have them yet (probably, customer service hadn't yet been informed of the recent timetable either at the point you asked for a refund).
2144  Bitcoin / Hardware / Re: ASIC vendor status on: January 15, 2013, 04:16:42 AM
Ok here is my experience and my thoughts on this. Bare with me.

I placed a pre order with BFL around Sept 10-12. I can't remember exactly and I don't think it really matters here anyways.

I placed a pre order because I wanted to try this bitcoin thing out but I did not really wanted to build a computer and run GPU's and make a mess where I live. I also did not want to use all the electricity associated with GPU's. FPGA's were still available but cost the same as the new ASIC's and used even less power. Why spend 600 dollars on 832mhz when you could spend 650 dollars on 30,000 MHZ .BFL looked like a nice compact and well built product.

I did not know about the criminal records and the past experience with delayed shipping of BFL. After finding out I still was willing to stay on.However I was very concerned after every delay.

After the first delay I became more involved in the forum while reading as much of the speculation going on here. I also had noticed there was absolutely no information about specs or pictures and to make my gut feeling worse NO ADDRESSES of these companies. Just PO boxes and that set off alarms

After October turned into November then December I was starting to post threats of cancelling my orders if there was ONE more delay. Jan 1 was my deadline and it was firm.

When Jan 1 came and gone and the same games were being played I fired off a refund request with one condition.

I will stay on and wait for the final product ONLY if I get a confirmed ship date. I also said If I don't get a reply in 3 days I will charge back.

 
You see I used PayPal to buy it but I used PayPal to charge my credit card. So NO ONE can screw me. I was protected by law.

Then in less than 24 hours they sent a refund back to my CC. I guess no ship date. By law they have to refund you back your money if no ship date was offered.

What that tell me is they are still not able to give me a confirmed ship date.

THEN right after the bASIC company imploded and I felt pretty dam proud that I got out. I slept well that night.

Then after BFL sends out an update which in my understanding is either an absolute lie or they now have 60 days to ship or refund ppls money.I think BFL saw the shit storm that was happening with bASIC and to stem the tide they had to offer a good update to keep their customers. I also have seen idiots asking on the BFL forum if they could add more to their orders. *facepalm*

I think BFL will not ship in 60 days or they would not have refunded my money.Besides I would not want to buy a highly untested unit that has been rushed to avoid a refund tsunami.

I feel compelled to place this to have other unsuspecting CON-sumers get taken for a ride as I did.

The ball is in your court. Becareful
Weren't you the one who asked for a refund though?  Of course they're going to give you a refund if you ask for one!  I don't see that as a sign that they aren't going to ship anything out.  If you aren't happy with the wait, they are more than willing to give you a refund and let you out.

Sounds like you made the right choice for your own level of stress/risk.  Obviously, ASICs aren't worth anyone having a heart attack over, so if it's causing you undue stress... The recent updates from BFL have made me very confident that they will deliver a product worthy of the specs they have been touting.  I haven't been stressed over this at all myself - the only money I invested is money I had already made with BFL FPGA's earlier on, so it wasn't a penny out of my own pocket if something went south.  I suppose that adds an extra peace of mind, in that it truly IS money I could afford to lose.  That and having a first-day preorder is pretty good incentive to stay onboard.  Wink
2145  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 15, 2013, 03:38:17 AM
6.4w per chip should not be a problem. As usual, they're not telling the truth.
In a QFN package?  With 8 chips on the same small PCB?  Do you have proof of this?  Is there a comparable product out in the wild (8 chips on one small PCB using roughly the same wattage in QFN form)?

Sure:

http://www.psitechnologies.com/products/powerqfn5x6.php

7 watts in a 5x6 mm package.
Who uses 8 of these chips on the same 3.5" x 3.5" PCB?

They don't want to be the company that releases marginally adequate products, and I can respect that decision.

You've made an excellent post here but I think the discussion needs to be carried on a bit farther.  Remember that BFL's selling shovels and that a customer's profit is greatly dependent on how early they can get mining.  BFL's profit is also greatly increased by shipping early and often with rapid iterations in the product.  There's a reason why you said in your post that you would have preferred a miner in November - it's because you and BFL both win more from it.  BFL's made a poor strategic choice here - they're in a market that calls for the "marginally adequate products" and they are creating something else entirely.
Without knowing all the details, it's tough to make a certain determination, as such a move might have caused BFL undue expense.  But you could be right...!
2146  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 15, 2013, 02:32:16 AM
I'm really getting tired of hearing pedestrian engineering mistakes being attributed to the difficulty of the bitcoin hashing algorithm as implemented in hardware.
Alright, fair enough.  One could certainly argue that the thermal problems should have been foreseen.  I am no expert, so I couldn't tell you - I can only take someone else's word for it one way or the other.

6.4w per chip should not be a problem. As usual, they're not telling the truth.
In a QFN package?  With 8 chips on the same small PCB?  Do you have proof of this?  Is there a comparable product out in the wild (8 chips on one small PCB using roughly the same wattage in QFN form)?
2147  Economy / Scam Accusations / Re: Bryan Micon's Butterfly Labs Scammer Investigation including Josh Zerlan on: January 15, 2013, 12:30:38 AM
Because they've been losing trust (and preorders/money) since December.  They would've stopped the scam and ran then rather than lose money continuing with it.

While its true they have lost trust throught the community, according to Inaba himself, hardly anyone has asked for a refund.

Also, how do you know they have not received a lot of orders in the past few months of uncertainty? Answer: you don't. I'm sure they had plenty more new orders in that time period... Not everyone reads these forums. Some rich guy whom just heard about bitcoin might come across some PR article BFL released about their ASICs or see their booth at CES and go straight to the website and buy 10 mini rigs... Etc.
Ok, I agree, it is speculative on both sides of the coin.  I am basing my speculation on the fact that I have seen 3-4 times as many people posting about receiving refunds for their BFL orders vs new posts saying they have ordered some.  But again, that is not telling any story with certainty.

Where did Josh state that hardly anyone has asked for a refund?
2148  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 15, 2013, 12:26:45 AM
why aren't they showing us the god damn blown chip then ....:/
They did - it was in the first set of pictures they released showcasing the PCB.

Pictures:  http://bitcoinmagazine.com/butterfly-labs-releases-more-asic-photos/


Someone please point it out for me, Those look like the same photos from awhile ago, I would assume that someone would've gone "LOOK!, ITS BROKEN!"

They did say something along those lines - Josh even acknowledged that in his post.
Quote
(you can see the bubbled chip in one of the pictures, I think someone pointed it out.)
2149  Economy / Scam Accusations / Re: Bryan Micon's Butterfly Labs Scammer Investigation including Josh Zerlan on: January 14, 2013, 11:40:04 PM
You do realise that if BFL is legit, you're going to look the biggest clown in the whole Bitcoin community for a very long time...
Especially with the video, scam accusations and constant tirade against BFL. You've made the whole BFL issue into Mircon vs BFL.

Either you'll come out smelling of roses or look a complete moron.

Yawn, people said the same thing about PirateAt40
is really stupid compare pirateat40 with BFL.

How so?

Pirate payed his investors monthly up until the day he defaulted to gain trust from the community and get more people to invest more money.

How is that any different from BFL selling FPGAs to gain the trust of the community and getting more people to invest more money in ASICs up until the day they run off with all the pre-order money?

The cases are similar if that's really what's going on here. Anyone that denies BFL's shadiness stands too much to lose if it turns out to be a scam and are blindly defending BFL. I have no ASIC pre-orders and can see things from an unbiased viewpoint. There is a possible chance BFL pre-orders are a scam, to say there is no chance would be foolish.
Because they've been losing trust (and preorders/money) since December.  They would've stopped the scam and ran then rather than lose money continuing with it.
2150  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 11:38:07 PM
why aren't they showing us the god damn blown chip then ....:/
They did - it was in the first set of pictures they released showcasing the PCB.

Pictures:  http://bitcoinmagazine.com/butterfly-labs-releases-more-asic-photos/

Quote
We made the decision to go with QFN in December. I can't really talk about our development process itself, but we have gone through extensive design and testing phases... at one point in early December we decided to look at a worst case scenario if the chips were in a really hot environment (you can see the bubbled chip in one of the pictures, I think someone pointed it out.). We paid a company out of California quite a bit of money to run a run of simulations under different scenarios on our boards, as well as if we made changes to various portions of the PCB if we could salvage the QFN package's thermal envelope. We were able to get the thermal loads down about 6C off the current mark, but we were still within single digits of the max temperatures of surrounding components once the heat started to migrate through the ground plane. If someone in a really hot area ran these things, the fan would be on full blast the entire time, and as dust and other detritus collected on the HSF the unit would start to overheat and throttle (or worst case, you'd get bubbled chips). The internal junction temp of our ASICs, if I recall is around 121C, however the MCU and a couple other components are around 100C or less if memory serves and we were butting up against that in some cases, in the 90's.

I've already touched on some of the roadblocks we've had. One of the more annoying ones was the diffraction issue ... for example, at 65nm if you try to make a square shape on a wafer, you can't just make a square shape on the mask, you'll end up with an ellipsis of some sort due to the wavelength of light. So you have to shape the mask to accommodate the wavelength so what ends up on the wafer is a square, though it looks very different on the mask. So you have to go through just about everything, making sure what you want is actually what ends up on the wafer... the delay this caused was not anticipated to the extent it delayed us and since this is a full custom, hand routed chip, basically it had to be gone over by hand from top to bottom.

Another delay we've had to endure is the fact that we have effectively tied the ASIC teams payment to the success of the chip. If the chip were to be a failure they don't get paid... so they have incentive to get it right but that has made them very cautious and slow to approve final masks (This is why we can refund all pre-orders we want and why we have the capital to do what we need to do without a failure putting us in bankruptcy).

Ultimately, it has all boiled down to the incredible complexity of the chip (I mean, look at that beast, it's all black in the shot it's so dense). If the chip were not so complex and so efficient there wouldn't be a heat issue, there wouldn't be the wariness of releasing the mask, etc... This is why I find it patently ridiculous that Tom kept claiming his 90nm sASIC or PnR chip would be 100w, it's ludicrous. Avalons claims are far more reasonable at 400w for their design and is why I haven't given them such a hard time. I think Avalon is going to run into some problems that we've run into, but I don't think they will be anything insurmountable, but I suspect it will delay them a bit while they try to figure out how to mount all the heat sinks or the giant heatsink they are going to need to keep the thing cool, and the board itself has to be massive. Tom was estimating 7 x 9" if I recall for his 16 chip 90nm process... the Avalon is 110nm with at least 80 chips I estimate... though I'm sure the chip footprint is much smaller, we're still talking about a bucket load of chips that all have to be cooled. If their package, and I think they are using QFN, is not letting enough heat out the top they are going to flood their thermal and ground planes with 300w+ of heat and cook everything in sight. We were fighting 60w of heat (granted, on a much smaller surface area) and it was a problem, I can't imagine trying to fight 300w of heat. For their sakes, I hope they have already considered these issues or it's going to be a nasty surprise the first time they turn a unit on and the chips start popping and letting the magic smoke out.
2151  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 11:25:06 PM
BFL says they have successfully tested their ASIC chip design then, and all is good to go on that front, it's just the chip package that needed some changing.

I'm not comfortable with how much information they're still hiding. They claim it's because they don't want the competition to see what they're doing, but that's B.S. if you're truly only weeks away from shipping the completed product.

Given all the commotion, it would be all too easy for them to disclose what they're doing and calm everyone down, but they don't. Suggests to me there's no progress to show.

Not that I'm complaining, but that's my observation.
What other information would you like to see?  Josh seems to be fairly open to answering additional questions at this point.

Also, what I said is wrong (I edited my post).  Josh clarified that the simulations done by the 3rd party company in December showed the chip itself was fine under all conditions, not that they had actually tested it with the updated PCB design.

So, here's what I piece together:
1) BFL received a small sample of QFN chips in October.
2) They decided to do additional testing to account for "worst case" scenarios.
3) They figured out that they were too close to the thermal limit, destroying their sample chips in the process.
4) They redesigned the PCB to hopefully alleviate the thermal concerns.
4) In December, they paid a company to test the redesigned PCB to see if they could sufficiently cool the QFN chips.  It turns out they could, but that the PCB would be partially acting as a heatsink and could potentially destroy some of the other components on the board due to heat.
5) They decide to go with flip-chip BGA at this point.
6) We're waiting on said flip-chip BGA.


...

It's not a scam.  All signs point towards a company inexperienced in producing Bitcoin ASICs ASICs attempting to produce Bitcoin ASICs. 
...

ftfy


Heat management is not exclusive to "Bitcoin ASICs."  Knowing a certain TDP will be problematic with a certain package and it's consequences to other components isn't rocket science, err, Bitcoin ASIC science.


I'm really getting tired of hearing pedestrian engineering mistakes being attributed to the difficulty of the bitcoin hashing algorithm as implemented in hardware.
Alright, fair enough.  One could certainly argue that the thermal problems should have been foreseen.  I am no expert, so I couldn't tell you - I can only take someone else's word for it one way or the other.
2152  Economy / Scam Accusations / Re: Bryan Micon's Butterfly Labs Scammer Investigation including Josh Zerlan on: January 14, 2013, 11:13:21 PM
Micon - I'll gladly take you up on a 1:1 bet that BFL will deliver.  I'd put down 20 BTC that BFL will deliver an ASIC miner by the end of 2013.
2153  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 11:07:11 PM
Nevermind...
2154  Economy / Lending / Re: TurMine Accel. Project - Need Multiple Investors/Financiers to Begin Next Week on: January 14, 2013, 10:37:47 PM
Now then, as far as monetizing such a client, I don't see it as possible to regain the $850 from casual GPU miners and experimenters only.  ASIC support will have to be included in the software, and if it is truly a step above everything else that is available for free, it should be cake to monetize at that point.  What ASIC miner WOULDN'T pay, say, $10 to gain an extra 2% efficiency?  At least initially, when difficulty is still relatively low?
The miner program doesn't contribute that much of a difference.  With GPU mining it is important to make a distinction between the mining client (minimal impact on performance) and the OpenCL kernel.  The days of 2% gains in the OpenCL kernel are long gone.   The code has been highly optimized and IIRC the most recent major change was something on the order of 0.1% performance increase.  The client itself has never been the performance bottleneck. 

With ASICs (and FPGA) the OpenCL kernel is replaced by the chip itself.  The client is just about management and reporting.   Further I would point out the OP isn't claiming any type of performance increase.


Correct.  We're focusing on end-user experience, which is why we're redeveloping the client, not the OpenCL kernel.  Like i've been saying, our hope is that this program will get beginners/general public more involved in Bitcoin.
Ah, ok.

How do you expect to be able to monetize this program?
2155  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 10:11:25 PM
So you get the same ammount BTC back from BFL.... What then will happen is that you will exchange them at current market price?!
You seem to forget that I had THE SAME BTC amount in my pocket BEFORE sending them to BFL. Since this SAME amount in BTC is my money I can do whatever I want whenever I want BEFORE or AFTER the BFL episode!
Take it to a courtroom, buddy.
2156  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 10:03:43 PM
That 121 is way too close to the failure at 125.. Even Xilinx starts to shut its chips down at 85.Then there is the issue of exactly what was the ambient when the die was reading 121... if it was the normal test temp of 85 deg c. then fine there is room in the design
but if it was measured at 25 deg. c... then we are all fucked.. the product is going to last less than a year.
Hence the reason they didn't go with the QFN chip packaging after all... they knew it wouldn't be a good idea based on these tests.

Good grief. The BFL website clearly puts the *price* in USD - and lists Bitcoin as one of the payment *methods*.
No, julz. Wrong assumption. If I use credit card, paypal, or bank wire to pay USD I'd use different methods to transfer same currency. What you fail to understand is that BTC is a different story. In addition to being a different payment "method" BTC is also a different currency. I have clearly shown, placing a screenshot above, that the BFL invoice is DENOMINATED both in $ and BTC!
How is BFL supposed to tell you how much BTC to pay without writing it on the invoice somewhere?  Of course it's going to be on the invoice - it's how much you paid!  That doesn't mean the sale was based on BTC at all.

When you go to their website, you order a product for $1,299.00, selecting the option to pay with Bitcoin.  You then click on the submit button (or whatever it is), and are told to pay the BTC equivalent.  This is NOT the same as the sale being denominated in BTC - it simply shows that you paid BTC for a sale denominated in USD.

Please do go to their order page and tell me how much a single costs in BTC.  From their order page.  That should set the record straight on whether their products are listed for sale denominated in BTC or not.
http://www.butterflylabs.com/order-form-bitforce-sc-single/

Again, take it to a courtroom if you think we are wrong!
2157  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 09:18:00 PM
Assume that buying stuff with your BTC was like selling your BTC for USD.
I can not assume something that is incorrect. I didn't sell my BTC for USD. BFL did. I don't have any contract with BitPay. BFL have. This is why only BFL can sell BTC to BitPay!

I don't know how you are reasonning, but for me, it was clear that it was refundable in USD.
Read, read, read... I thought you have read all my reasoning so far and this is why you are annoyed?! For me, it was clear that I'm paying in BTC and it was refundable in the currency and amount that was originally paid.
You are wrong.  A court would not agree with you on this.  BFL's orders were priced in USD, therefore you will receive a refund in USD.  If you believe differently, take it to a courtroom and prove us all wrong!
2158  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 09:06:39 PM
Wasn't the picture of the bubbled chip posted in late-ish October? Did you blow it up in October than then have the simulations done in December, and then decided to switch away from QFN?
It sounds like that's about how it went, yeah.  They got the QFN prototypes, figured out they couldn't cool them properly as they thought they could, did some "worst case scenario" self testing, bubbled a chip, decided to have an outside company do some similar testing in December, and then concluded they couldn't properly cool a QFN chip in a heated environment.

If that's the case and they knew about the problems with the QFN in early/mid-Oct, what was going on for the last half of October and November before they had the consultants run thermal simulations and start the move to a FC package in December?
Did they have an initial batch in Oct that ran too hot and blew the chip, tried another wafer run through November expecting to ship in December that still had too many issues, then ran the simulations and decided to switch to FC?
Sounds like a distinct possibility to me...!
2159  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 08:56:20 PM
More details on the QFN packaging and reasons for delays:

Quote
We made the decision to go with QFN in December. I can't really talk about our development process itself, but we have gone through extensive design and testing phases... at one point in early December we decided to look at a worst case scenario if the chips were in a really hot environment (you can see the bubbled chip in one of the pictures, I think someone pointed it out.). We paid a company out of California quite a bit of money to run a run of simulations under different scenarios on our boards, as well as if we made changes to various portions of the PCB if we could salvage the QFN package's thermal envelope. We were able to get the thermal loads down about 6C off the current mark, but we were still within single digits of the max temperatures of surrounding components once the heat started to migrate through the ground plane. If someone in a really hot area ran these things, the fan would be on full blast the entire time, and as dust and other detritus collected on the HSF the unit would start to overheat and throttle (or worst case, you'd get bubbled chips). The internal junction temp of our ASICs, if I recall is around 121C, however the MCU and a couple other components are around 100C or less if memory serves and we were butting up against that in some cases, in the 90's.

I've already touched on some of the roadblocks we've had. One of the more annoying ones was the diffraction issue ... for example, at 65nm if you try to make a square shape on a wafer, you can't just make a square shape on the mask, you'll end up with an ellipsis of some sort due to the wavelength of light. So you have to shape the mask to accommodate the wavelength so what ends up on the wafer is a square, though it looks very different on the mask. So you have to go through just about everything, making sure what you want is actually what ends up on the wafer... the delay this caused was not anticipated to the extent it delayed us and since this is a full custom, hand routed chip, basically it had to be gone over by hand from top to bottom.

Another delay we've had to endure is the fact that we have effectively tied the ASIC teams payment to the success of the chip. If the chip were to be a failure they don't get paid... so they have incentive to get it right but that has made them very cautious and slow to approve final masks (This is why we can refund all pre-orders we want and why we have the capital to do what we need to do without a failure putting us in bankruptcy).

Ultimately, it has all boiled down to the incredible complexity of the chip (I mean, look at that beast, it's all black in the shot it's so dense). If the chip were not so complex and so efficient there wouldn't be a heat issue, there wouldn't be the wariness of releasing the mask, etc... This is why I find it patently ridiculous that Tom kept claiming his 90nm sASIC or PnR chip would be 100w, it's ludicrous. Avalons claims are far more reasonable at 400w for their design and is why I haven't given them such a hard time. I think Avalon is going to run into some problems that we've run into, but I don't think they will be anything insurmountable, but I suspect it will delay them a bit while they try to figure out how to mount all the heat sinks or the giant heatsink they are going to need to keep the thing cool, and the board itself has to be massive. Tom was estimating 7 x 9" if I recall for his 16 chip 90nm process... the Avalon is 110nm with at least 80 chips I estimate... though I'm sure the chip footprint is much smaller, we're still talking about a bucket load of chips that all have to be cooled. If their package, and I think they are using QFN, is not letting enough heat out the top they are going to flood their thermal and ground planes with 300w+ of heat and cook everything in sight. We were fighting 60w of heat (granted, on a much smaller surface area) and it was a problem, I can't imagine trying to fight 300w of heat. For their sakes, I hope they have already considered these issues or it's going to be a nasty surprise the first time they turn a unit on and the chips start popping and letting the magic smoke out.

https://forums.butterflylabs.com/bfl-forum-miscellaneous/690-13-jan-2013-asic-update-discussion-thread-6.html

Wasn't the picture of the bubbled chip posted in late-ish October? Did you blow it up in October than then have the simulations done in December, and then decided to switch away from QFN?
It sounds like that's about how it went, yeah.  They got the QFN prototypes, figured out they couldn't cool them properly as they thought they could, did some "worst case scenario" self testing, bubbled a chip, decided to have an outside company do some similar testing in December, and then concluded they couldn't properly cool a QFN chip in a heated environment.
2160  Bitcoin / Hardware / [Archive] BFL trolling museum on: January 14, 2013, 08:31:43 PM
More details on the QFN packaging and reasons for delays:

Quote
We made the decision to go with QFN in December. I can't really talk about our development process itself, but we have gone through extensive design and testing phases... at one point in early December we decided to look at a worst case scenario if the chips were in a really hot environment (you can see the bubbled chip in one of the pictures, I think someone pointed it out.). We paid a company out of California quite a bit of money to run a run of simulations under different scenarios on our boards, as well as if we made changes to various portions of the PCB if we could salvage the QFN package's thermal envelope. We were able to get the thermal loads down about 6C off the current mark, but we were still within single digits of the max temperatures of surrounding components once the heat started to migrate through the ground plane. If someone in a really hot area ran these things, the fan would be on full blast the entire time, and as dust and other detritus collected on the HSF the unit would start to overheat and throttle (or worst case, you'd get bubbled chips). The internal junction temp of our ASICs, if I recall is around 121C, however the MCU and a couple other components are around 100C or less if memory serves and we were butting up against that in some cases, in the 90's.

I've already touched on some of the roadblocks we've had. One of the more annoying ones was the diffraction issue ... for example, at 65nm if you try to make a square shape on a wafer, you can't just make a square shape on the mask, you'll end up with an ellipsis of some sort due to the wavelength of light. So you have to shape the mask to accommodate the wavelength so what ends up on the wafer is a square, though it looks very different on the mask. So you have to go through just about everything, making sure what you want is actually what ends up on the wafer... the delay this caused was not anticipated to the extent it delayed us and since this is a full custom, hand routed chip, basically it had to be gone over by hand from top to bottom.

Another delay we've had to endure is the fact that we have effectively tied the ASIC teams payment to the success of the chip. If the chip were to be a failure they don't get paid... so they have incentive to get it right but that has made them very cautious and slow to approve final masks (This is why we can refund all pre-orders we want and why we have the capital to do what we need to do without a failure putting us in bankruptcy).

Ultimately, it has all boiled down to the incredible complexity of the chip (I mean, look at that beast, it's all black in the shot it's so dense). If the chip were not so complex and so efficient there wouldn't be a heat issue, there wouldn't be the wariness of releasing the mask, etc... This is why I find it patently ridiculous that Tom kept claiming his 90nm sASIC or PnR chip would be 100w, it's ludicrous. Avalons claims are far more reasonable at 400w for their design and is why I haven't given them such a hard time. I think Avalon is going to run into some problems that we've run into, but I don't think they will be anything insurmountable, but I suspect it will delay them a bit while they try to figure out how to mount all the heat sinks or the giant heatsink they are going to need to keep the thing cool, and the board itself has to be massive. Tom was estimating 7 x 9" if I recall for his 16 chip 90nm process... the Avalon is 110nm with at least 80 chips I estimate... though I'm sure the chip footprint is much smaller, we're still talking about a bucket load of chips that all have to be cooled. If their package, and I think they are using QFN, is not letting enough heat out the top they are going to flood their thermal and ground planes with 300w+ of heat and cook everything in sight. We were fighting 60w of heat (granted, on a much smaller surface area) and it was a problem, I can't imagine trying to fight 300w of heat. For their sakes, I hope they have already considered these issues or it's going to be a nasty surprise the first time they turn a unit on and the chips start popping and letting the magic smoke out.

https://forums.butterflylabs.com/bfl-forum-miscellaneous/690-13-jan-2013-asic-update-discussion-thread-6.html
Pages: « 1 ... 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 [108] 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 ... 405 »
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!