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Bitcoin => Hardware => Topic started by: dako44 on September 27, 2015, 07:11:38 PM



Title: Dragon Miner A1 module hashing at unusual amounts
Post by: dako44 on September 27, 2015, 07:11:38 PM
To make a long story short, I've got this Dragon Miner A1. One of the modules says it hashes at 750gh, but in reality it just isn't working. So, I did some research and found out that one of the VRM chips is probably bad (If my theory is wrong please correct me) and needs replacing. So the module apart today and discovered 2 VRM chips, one is a 1.8V and the other is a 3.3V. They have writing on them and I searched it up and found some, but the last string of numbers is different on all of them. Does the last string of numbers matter? I am also not currently sure of the amperage on the original chips. So if anyone knows that info please share that with me.

The 1.8V one is as follows: AMS1117 1.8V H418KE
The 3.3V one is as follows: AMS1117 3.3V H421PE

If the last set of numbers matters could someone tell me what they mean?

Thanks,
dako44



Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: unamis76 on September 27, 2015, 07:24:27 PM
You'd probably get more help on Mining Hardware (https://bitcointalk.org/index.php?board=76.0) or perhaps on this (https://bitcointalk.org/index.php?topic=545642.0) thread. This sub-forum is for tech support related to Bitcoin, the blockchain and Core


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: J4bberwock on September 27, 2015, 08:28:11 PM
To make a long story short, I've got this Dragon Miner A1. One of the modules says it hashes at 750gh, but in reality it just isn't working. So, I did some research and found out that one of the VRM chips is probably bad (If my theory is wrong please correct me) and needs replacing. So the module apart today and discovered 2 VRM chips, one is a 1.8V and the other is a 3.3V. They have writing on them and I searched it up and found some, but the last string of numbers is different on all of them. Does the last string of numbers matter? I am also not currently sure of the amperage on the original chips. So if anyone knows that info please share that with me.

The 1.8V one is as follows: AMS1117 1.8V H418KE
The 3.3V one is as follows: AMS1117 3.3V H421PE

If the last set of numbers matters could someone tell me what they mean?

Thanks,
dako44



here is the datasheet of the LDO chips:

http://www.advanced-monolithic.com/pdf/ds1117.pdf

I didn't check the pinout, but it's very likely that they are compatible with ncp1117, ncv1117, and many other "1117" LDOs, all outputting 1A.
But first, you'll need to check if the Vout is out of specs.
Center pin is the vout.
Most of the time, you can use almost any screw from the heatsink as a ground reference (or simply use pin 1 of the LDO).

I'm not too familiar with the dragon units, but I'm not sure the LDOs are at fault, maybe just the asics that went bad.
from what I remember (but I may be wrong), the I/O are all chained together. I don't know what will happen if one chip in the chain fails.


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: dako44 on September 27, 2015, 08:44:55 PM




here is the datasheet of the LDO chips:

http://www.advanced-monolithic.com/pdf/ds1117.pdf

I didn't check the pinout, but it's very likely that they are compatible with ncp1117, ncv1117, and many other "1117" LDOs, all outputting 1A.
But first, you'll need to check if the Vout is out of specs.
Center pin is the vout.
Most of the time, you can use almost any screw from the heatsink as a ground reference (or simply use pin 1 of the LDO).

I'm not too familiar with the dragon units, but I'm not sure the LDOs are at fault, maybe just the asics that went bad.
from what I remember (but I may be wrong), the I/O are all chained together. I don't know what will happen if one chip in the chain fails.

So to clarify, test the chips to make sure they are outputting 1.8 and 3.3 volts respectively, then go from there.

And it shouldn't matter on the model as long as it is 1.8V and 1A or 3.3V and 1A?


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: J4bberwock on September 27, 2015, 09:22:01 PM




here is the datasheet of the LDO chips:

http://www.advanced-monolithic.com/pdf/ds1117.pdf

I didn't check the pinout, but it's very likely that they are compatible with ncp1117, ncv1117, and many other "1117" LDOs, all outputting 1A.
But first, you'll need to check if the Vout is out of specs.
Center pin is the vout.
Most of the time, you can use almost any screw from the heatsink as a ground reference (or simply use pin 1 of the LDO).

I'm not too familiar with the dragon units, but I'm not sure the LDOs are at fault, maybe just the asics that went bad.
from what I remember (but I may be wrong), the I/O are all chained together. I don't know what will happen if one chip in the chain fails.

So to clarify, test the chips to make sure they are outputting 1.8 and 3.3 volts respectively, then go from there.

And it shouldn't matter on the model as long as it is 1.8V and 1A or 3.3V and 1A?

you need to check pinout of the part you plan to buy:
pin1 = gnd
pin2=Vout
pin3=Vin

NCP1117, NCV1117, LD1117A, LT1117 are compatible if yours are sot223 package

but first, check voltage output


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: dako44 on September 27, 2015, 09:24:53 PM




here is the datasheet of the LDO chips:

http://www.advanced-monolithic.com/pdf/ds1117.pdf

I didn't check the pinout, but it's very likely that they are compatible with ncp1117, ncv1117, and many other "1117" LDOs, all outputting 1A.
But first, you'll need to check if the Vout is out of specs.
Center pin is the vout.
Most of the time, you can use almost any screw from the heatsink as a ground reference (or simply use pin 1 of the LDO).

I'm not too familiar with the dragon units, but I'm not sure the LDOs are at fault, maybe just the asics that went bad.
from what I remember (but I may be wrong), the I/O are all chained together. I don't know what will happen if one chip in the chain fails.

So to clarify, test the chips to make sure they are outputting 1.8 and 3.3 volts respectively, then go from there.

And it shouldn't matter on the model as long as it is 1.8V and 1A or 3.3V and 1A?

you need to check pinout of the part you plan to buy:
pin1 = gnd
pin2=Vout
pin3=Vin

NCP1117, NCV1117, LD1117A, LT1117 are compatible if yours are sot223 package

but first, check voltage output


Alrighty! Thanks for the help. :)


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: dako44 on September 29, 2015, 08:46:24 PM
UPDATE: Tested the LDOs, they were outputting the right amount of voltage on both of them. Is one of the ASIC chips bad then?


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: notlist3d on October 02, 2015, 03:25:29 AM
Could someone maybe link somewhere to buy a new module? Im not sure wjere to get one of these replaced. Lktec didnt respond to emails.


They no longer make the A1.   You will be stuck to second hand channels most likely.   So you can check here on the forum for a 1t module.  Most likely that module with the high hashing will not be the same it's chances are a dud at this point. 

You might give Mr. Lee a pm and see if he has any - https://bitcointalk.org/index.php?topic=934581.0 .  It's been a long time but at one point he hosted a lot of A1's.  Dont know if he still has some parts or not but hes your best chance of a "big" seller having any.  If he does not hit the hardware board.   

But in all honesty chances are shipping and what you get charged on module will cost more then it will mine.  Do some ROI math but you might be better off just running 3 modules.


Title: Re: Dragon Miner A1 module hashing at unusual amounts
Post by: dako44 on October 02, 2015, 03:33:05 AM
I might pm him but yeah at this point I'm kinda tired of messing with it. I may just run it with 3. Thanks for the help though.