Bitcoin Forum

Bitcoin => Hardware => Topic started by: Biomech on March 26, 2014, 10:11:54 AM



Title: AMT (HEX16B based miner) let out the magic smoke :(
Post by: Biomech on March 26, 2014, 10:11:54 AM
Hello Y'all.

I have two Technobit HEX16B boards. One of them sparked, shut down the PSU, and has quit. There are two tiny little components that I think are resistors in positions four and five from the left of the molex connector. Any of you nice folks know what they are, where I can get 'em, and how much of a bitch the repair will be? Nothing else appears to have burned on the board. The bitfury chips were barely warm when the incident occured.


Title: Re: HEX16B let out the magic smoke :(
Post by: dogie on March 26, 2014, 11:17:34 AM
If they went with a bang and are rectangle things that look like a resistor, then its a capacitor :P


Title: Re: HEX16B let out the magic smoke :(
Post by: Biomech on March 26, 2014, 11:23:56 AM
If they went with a bang and are rectangle things that look like a resistor, then its a capacitor :P

More of a fzzzt :D They could very well be. Little rectangles, whole bunches of 'em. I haven't done component level work in decades, they didn't make the shit that small when I was young :D
I'll snap a pic in a bit. Maybe that'll help.


Title: Re: HEX16B let out the magic smoke :(
Post by: dogie on March 26, 2014, 12:17:30 PM
By bang I mean fireworks, because they hold so much energy in a relatively small amount of space. If a resistor died, something might overvolt if it somehow shorted but that's about it.


Title: Re: HEX16B let out the magic smoke :(
Post by: Biomech on March 26, 2014, 12:30:09 PM
By bang I mean fireworks, because they hold so much energy in a relatively small amount of space. If a resistor died, something might overvolt if it somehow shorted but that's about it.
Sorry, thought you meant actual noise.

Yeah, I am actually well versed in electronics... 20 years ago :D Back then a cap would have made some serious noise. I think you're right, and I'll u/l a picture as soon as my phone decides to sync with Drive. It heated up and threw some sparks, totally demolished one of the beasties in question and melted the other one.

My biggest issue is how dafuq does one solder something that freaking small? I can do pretty fine work, but not that fine. Second biggest issue is figuring out what the parts are and where to get 'em :P


Title: Re: HEX16B let out the magic smoke :(
Post by: TheRealSteve on March 26, 2014, 12:37:10 PM
My biggest issue is how dafuq does one solder something that freaking small? I can do pretty fine work, but not that fine.
http://www.theledart.com/blog/archives/1301

Second biggest issue is figuring out what the parts are and where to get 'em :P
digikey, farnell/element14.. amazon.. ebay, if you must.  Might be worth it to check if there's a hacker/makerspace near you that may already do SMD/SMT electronics and have some of the needed components (they're usually pretty standard.. capacitors for decoupling, resistors as pullups/downs/passive current limiters) in stock that you can get.. and they may also have more appropriate equipment should you need it :)


Title: Re: HEX16B let out the magic smoke :(
Post by: Biomech on March 26, 2014, 12:42:08 PM
My biggest issue is how dafuq does one solder something that freaking small? I can do pretty fine work, but not that fine.
http://www.theledart.com/blog/archives/1301

Second biggest issue is figuring out what the parts are and where to get 'em :P
digikey, farnell/element14.. amazon.. ebay, if you must.  Might be worth it to check if there's a hacker/makerspace near you that may already do SMD/SMT electronics and have some of the needed components (they're usually pretty standard.. capacitors for decoupling, resistors as pullups/downs/passive current limiters) in stock that you can get.. and they may also have more appropriate equipment should you need it :)

Thanks!
I gotta bag it for tonight, but that looks like I got some serious learnin' to do. Now to get the part ID'd.. well, tomorrow. I'm off to bed.

Thanks again for the help, gentlemen.


Title: Re: HEX16B let out the magic smoke :(
Post by: Zich on March 26, 2014, 12:57:31 PM
That was SMD 0805 capacitor 10 uF/16V


Title: Re: HEX16B let out the magic smoke :(
Post by: Gator-hex on March 26, 2014, 02:39:29 PM
What clock/volt where you trying to run them at, how old were they, just so the community can know where the overclock limit/life span is.

I've never tried above the default 540/900 because I've not seen much feedback on pushing the clocks.

I've had 6 running on 1800rpm quiet fans for 3 months now without issue.

Thanks for any info you can add to help us understand how it died.


Title: Re: HEX16B let out the magic smoke :(
Post by: marto74 on March 26, 2014, 08:12:44 PM
The problem with AMT devices based on our boards is that they use less than half of the heat sink cooling area with poor airflow provided by samll fans
most probably overheating.
Please be correct and state that it si technobit board in AMT case and with tiny heat sink and poor ventilation !!!


Title: Re: HEX16B let out the magic smoke :(
Post by: Biomech on March 26, 2014, 09:09:58 PM
The problem with AMT devices based on our boards is that they use less than half of the heat sink cooling area with poor airflow provided by samll fans
most probably overheating.
Please be correct and state that it si technobit board in AMT case and with tiny heat sink and poor ventilation !!!
Hey Martin. I was unaware that there was any difference, Yeah, this is an AMT. I actually think it shorted due to them going psycho with thermal paste. Since you are looking.. 5 little devices to the left of power, above the screw hole with the molex connector facing you. 4 and 5 from left sparked and died. No other apparent damage. What are the devices?

Also, the other is no longer in the case, and to the previous poster, it was set to default. I really don't thunk you can use this for mtbf calcs. More of an accident than a valid metric. Martin makes good boards. AMT got crazy with thermal grease, which I am pretty sure was the cause of this.

edited for android induced typos


Title: Re: HEX16B let out the magic smoke :(
Post by: Biomech on March 26, 2014, 09:14:37 PM
That was SMD 0805 capacitor 10 uF/16V
Thanks.


Title: Re: HEX16B let out the magic smoke :(
Post by: marto74 on March 26, 2014, 09:17:57 PM
The problem with AMT devices based on our boards is that they use less than half of the heat sink cooling area with poor airflow provided by samll fans
most probably overheating.
Please be correct and state that it si technobit board in AMT case and with tiny heat sink and poor ventilation !!!
Hey Martin. I was unawre that there was any difference, Yeah, this us an AMT. I actually think it shorted due to them going psycho with thermal paste. Since you are looking.. 5 little devices to the left of power, above the screw hole with the molex conbector facing you. 4 and 5 from left sparked and died. No other apparent damage. What are the devices?

Also, the other is no longer in the case, and to the previous poster, it was set to default. I really don't thunk you can use this for mtbf calcs. More of an accident than a valid metric. Martin makes good boards. AMT got crazy with thermal grewse, which I am pretty sure was the cause of this.
NO the thermal paste is not an issue here.
For thermal paste is POOH's law more is more ;)
The problem is overheating and dead transistor ( you do not see it ) and dead capacitors on the dc-dc psu.
Please @ least change the subject of the tread to AMT( technobit) hex16B ....


Title: Re: HEX16B let out the magic smoke :(
Post by: Biomech on March 27, 2014, 01:01:23 AM
The problem with AMT devices based on our boards is that they use less than half of the heat sink cooling area with poor airflow provided by samll fans
most probably overheating.
Please be correct and state that it si technobit board in AMT case and with tiny heat sink and poor ventilation !!!
Hey Martin. I was unawre that there was any difference, Yeah, this us an AMT. I actually think it shorted due to them going psycho with thermal paste. Since you are looking.. 5 little devices to the left of power, above the screw hole with the molex conbector facing you. 4 and 5 from left sparked and died. No other apparent damage. What are the devices?

Also, the other is no longer in the case, and to the previous poster, it was set to default. I really don't thunk you can use this for mtbf calcs. More of an accident than a valid metric. Martin makes good boards. AMT got crazy with thermal grewse, which I am pretty sure was the cause of this.
NO the thermal paste is not an issue here.
For thermal paste is POOH's law more is more ;)
The problem is overheating and dead transistor ( you do not see it ) and dead capacitors on the dc-dc psu.
Please @ least change the subject of the tread to AMT( technobit) hex16B ....

Sure. Will do that in just a moment. When you first called me on it I was in the hospital waiting room (thus all the typos which I'm about to fix.) I'm back home now. Android phones are cool, but typing on them is a cast iron bitch.

Just so anybody reading this knows: There was NO intent to dis Technobit here. I frankly thought either I or AMT caused this. I was and am just looking for a bit of help.

Back at you, Martin Based on what you just said there, do you think it worth trying to fix the board?