I think cointerra is running into exactly the same problem BFL did: Chips tend to use more power than you think, and this can really upset a board layout.

In their case, I read somewhere they're hashing at 75% expected speed with more power being used. This winds up stressing the 1 volt supply lines, and since people seem to insist on running FETs in parallel (need more power, just ADD MORE FUCKING FETS) the supplies either become unstable or blow up in a cool zipper fashion.

I don't understand that bit; I've worked with electric motor controllers in the 30-150kw range and the Curtis 300 amp controllers had this hilarious bank of 30a FETs down a rail. Problem is when a FET gets warm it pulls more power, which means the rail goes unstable then the FETs start blowing up. Hilarity ensues when top and bottom rails short and you get to see if your 500a fuse is really DC rated to 30,000 amps interrupt rated.

Ahem. The right way to do it is with IGBTs, gated by a 2708 type power gate driver. A good single 300 amp IGBT would handle the 1 volt switching with very low voltage loss (ie: less heat) and can be water cooled. But do people do this? NOOOOOOOOOOO!.

So they have to redesign their board for more chips, more crosstalk, and a beefalo style power subsystem.

Done, sent from my 15eT8 wallet.

No this chick was creepier than goatse, she was hot as hell. Then.......

I believe in paying for services rendered. Keep up the demented things, and thanks again!

C

I will have to say, I am quite impressed with the chick on redtube who has a bovine speculum in her ass. It took an image of cute baby Hitler to knock that one out of my brain.

But I would have to say Pia Zadora.

C

I'm serious, that image has been haunting my brain for a week. Blew out goatse, now gone and replaced by this.

And I realize I should pay you for your work. Is that your btc wallet, if so I'll drop you .01btc for your assistance.

Thanks!
L

Thank you for posting this. That image totally knocked out of my mind the hot chick on redtube with the bovine speculum in her ass.

I really, really do appreciate this.

Quick update: Just finished doing two more jalapeno upgrades, one was a 5gh unit and the other was an older style 7.5gh unit.

The first unit got 4 chips and went to 22gh without issues. Errors are below .5%, which helps to minimize heat issues. Also when I flashed it I found that a speed of 5 produced the best results, going to 6 or 7 caused one of the original chips to drop down to 6 engines. Going to 5 brought up 14, so even with the reduced clock speed it still performed better. And the heat load is *greatly* reduced. Result is a 6 chip unit hashing in the 50's temp wise with a stock heat sink and fan.

The second unit (manebjorn's) had two of the original taller chips, and hashed at a good 7.8gh after a code flash. The user thought the unit was broken, but it turned out to just be a dud power supply. Took it to 5 chips, and it's now hashing at a solid 20gh with stock heat sink, fan, at 50c. Which is excellent. I did put a grille on top of the fan to keep the blades from breaking, but aside from that it's totally stock.

Current success rate on these chip installs is 100%, the trick seems to be putting chips on one at a time. I could probably try placing two chips then heating, but I'm always concerned the chip will shift, so I have to do a cool down/test between each chip add.

Chris

Disclaimer: I am not an electrician. I am a moron.

That said, the problem normally isn't plugging a higher rated power distribution device into a lower rated socket, it's plugging a lower rated power distribution device into a higher rated socket.

The reason is if you pull too much power through a higher rated dist device, the lower rated breaker in the panel will open. Boo hoo. However if you have a 30 amp socket and you plug a 15 amp electrical cord into it, then a short in the device will not trip the breaker before the cord heats up and hilarity ensues.

Does that help?

C

And no one was forced by anyone to send in a pre-order. End users chose to send them money, that's life.

That's not relevant unless he was explicitly expected to post things to this thread by BFL. *I* was sent "free hardware" from BFL, yet I post under no impramateur from them.

C

* My free hardware was a single old-style heat sink sent to me so I could see if it cooled better than the AL sinks on Jalapenos. As I posted in my threads, it does work better due to less airflow obstruction. This is completely irrelevant to the question of "did BFL screw people", my independant research showed that they ran into a big problem and bent over backwards to provide equipment that met promised specifications, even to the extent of shipping a lot of extra stuff and taking a loss.

All other equipment in my research was either purchased by me at full price/ebay prices, or was donated to me by other users (chips, a blown board, beer).

They're also hashing at 1.5gh, and pulling significantly more power to do it. Go figure, recommend you plug that into the question.

Interesting: I don't like the Corsair 750m as much as the 500. Although it does have more power without a doubt, the ribbon cables it uses are really kind of undersized in terms of wire gauge. There are "four" PCIe plugs, but two of them are on the end of each ribbon cable, and the gauge of the wire going to them both is a bit smaller than the gauge of the 500's single plug. Result is what's the frigging point?

Right now I have a 48gh single running on one side, and a 32gh single+35gh chili running on the other. The second wire is getting a bit warm going back to the power supply, which of course means overload and *inefficiency*. And although I can run one 24gh overclocked jally on a 12 volt line, I can't run the 20gh jally on the same line, different plug because *it* gets a bit warm.

Drat. So if you're looking for power supplies, 2 500 watt units are going to be better than a 750 in more ways than one.

C

See, that's the error people make in thinking: If that person had not spent the money for the two pizzas, then that news story of "hey, someone actually converted this digital stuff for FOOD" would never have been aired. And people would never have heard of Bitcoin, or thought that it the idea would have any merit.

And the value of Bitcoin today would equal the value of flooze or something. You can never change something in the past without changing the present. People just do not seem to get that.

Just got the 750. The 500 was not happy; things are much more merry on a 750 watt unit. And I now have more room for some more singles.

Other than that everything is working fine. Still a solid 48gh, that one I fixed is at a solid 31, just keeping an eye out for some chips to boost it to 60.

Apple is the Blackberry of tomorrow. :-)

Bought power supplies, parts, etc... Even a kettle. Bitcoin is now being used as money here.

C

Speaking of which I have a dead jally in the shop that is also getting 2 more chips. Bad power supply, everything else fine.

C

Likewise if you offer to deliver the product, the customer "refuses" and the items delivered meet the specs then what the heck else do you want?

If you make a mistake on an investment you don't get to call for a "do over". That would be one hell of an investment strategy though....

Everything I have ordered from BFL has arrived. And oddly enough I can see where they delivered me *more* product to meet the exact terms of what I ordered (4.5gh jalapeno that should have not been expandable. They shipped me a 5gh unit with the capability of going to 32gh. That's not bad)

They're crap, but the single/30 power supplies aren't bad. Except for the solder joints on the wires to the unit, I think what happens is you get a cold solder on one of the six wires, it goes high, and the remaining 4 are too small to power the unit properly.

My solution is Corsair 600/750's.

C

Tiger Direct, and it's not the best possible price (I could have gotten it for $10 less at Amazon) but:

a) I want to support people accepting bitcoin
b) I want to generate more commerce activity in bitcoin
c) It's free money, costs me nothing!

:-) Actually the 12 cents will come out of an upgrade profits, so technically my business is becoming self-sustaining.

C

Interesting thing to note: Last night my 32gh Jalapeno blew up it's power supply (a crummy 300 watt ATX one from Ebay, $20) so I put it on my CX500 along with a high power burning Chili and the 48gh single. The single dropped off line this afternoon and went to zero gh hash rate, which was very odd. So I moved the 20gh unit onto the the CX500, moved the Jally to the other CX500 and now everything is stable.

So it does appear that power supply issues (yes, the 500 watt Corsair was overloaded) can cause oddball issues. I just ordered a 750 watt Corsair to come by Friday, that will fix the problem long term:

Also note that crappy power supplies are not worth it for miners.

C

Well, 12 bitcents will get a nice new Corsair delivered by Friday. We shall see how it looks :-)

Actually I think this is my first failure, not bad. I'll order a 750 watt Corsair from Tiger and pay with some bitpennies. This stuff can support itself.

I just keep adding. stuff. My electricity bill is going to be fearsome.

C