Topic: (Review/Guide) AvalonMiner 821 11.0 Th/s, 1200W Bitcoin (SHA-256) ASIC miner - page 2. (Read 2940 times)

Will you start a new thread for your A841 review and testing? Do you have an estimated ship date for your A841? Are you in the April 15th-April 30th batch that I see mentioned on the BlokForge website, or perhaps something sooner?

I am very interested in how this plays out, as you can probably tell by my questions....

I'll let you guys know and I will do a thorough testing for the A841 to find out what is the best performance we can get out of it.
Phil, with your estimate I think you are quite close to what could be the actual number for the power efficiency when the voltage offset is -2.

Nice work.  I got a notice for the 841's but I will not be buying in bulk.

They say the 841 does 0.099 watts per gh on 0 offset   I am thinking it will do 0.092 on  -2 offset

Let us know when you get one.

No issues so far, it just keeps on hashing steady. 

Any new updates on your experience with Avalon 821? 

I wanted to try out this new platform and the review is now also available in the Steemit blogging website.
Link: https://steemit.com/review/@hagssfin/review-guide-avalonminer-821-11-0-th-s-1200w-bitcoin-sha-256-asic-miner

I'm still going to continue as before. Posting here at the Bitcointalk.org forum is my priority number 1.

You seem to have a pretty good relationship with Canaan.  I think it would be worthwhile to ask if the undervolt stuff is good for these miners or not.  

Here is a copy of an email that I got from then when I asked about potential bugs in the firmware.

"e.g. there is an option to set a -2 to 1 voltage offset, this worked with the 741s, but with the 821, that option is there in the web interface, but the command that is actually used to start the miner,
*always* forces the 0 offset and ignores the value set in the web UI.
>> This option is for A741, sorry for we didn't delete this function from A821's firmware.

There is one other around the min fan speed, it defaults to 100%, what probably makes more sense is to set to that 50 by default.  The outlet temperature is set to 70, where as on the 741 it was 90, because of this with the default min fan set to 100%, the fans run at 100%  speed whether they need to or not.
>> We locked the fan speed in the A821 firmware since its chips cannot take high temperature.
"

You'll see my question and their response..  It is worthy of note - there are *2* voltage options on the 821, the 741 only had one.  It could be they referenced the other one when they sent that I just don't know.  I know it works if you change it to add to the commandline, but what I don't know is if there might be damage that could be caused by using it?

Just a thought.

Yes. Steven has told that the A841 power efficiency should be even better. 

So the -2 setting is  very low .1064 per gh. At the wall.

This is better then the s-9

The 841 May do 0.0975 at the wall.

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(Moderator's note: This post was edited by frodocooper to trim the quote from HagssFIN.)

I have now updated the extra chapter 'extra) Testing different voltage offset values and writing down miner performance results'.
This time the test was successful and I got some nice results.  

Link: https://bitcointalksearch.org/topic/m.30217488

Thanks for your comments lrowland21093 & akadamson!

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I have also updated the nicely formatted version with all the recent changes.

The nicely formatted version of this review/guide (February 25, 2018 version) is available for download in my Mega cloud.

Link:
https://mega.nz/#!Zl8zlRSZ!8JKeDllHjtBPUW3ctF3Rap-Dau4TqAVPR6Voy-bS4B0

I do have a sorcerer hooked up to this one, another PSU is coming today for the other one.  I base it off listening from the other side of the door as well as from the street as the hot air is exhausted out with the fan...it's not a whole lot quieter but it is noticeable. 

A little... ... Sheesh the sorcerers are louder!  lol

These guys are a little quieter than the s9's...to my untrained and slightly deaf ears.   

Here are the 8 options - Make sure you select the Avalon8 branch to see the version shipped with that firmware

starting at line ~1500

https://github.com/Canaan-Creative/cgminer/blob/avalon8/cgminer.c

Thanks! This is a good observation.
I feel stupid not checking if it actually applied the changed voltage offset value.
It is so easy to see at the Processes page.

I will re-do this 'extra chapter' I did later on and test it by inserting voltage offset values
from -2 to +1 using the Cgminer command --avalon8-voltage-level-offset -2.

I posted a note about the voltage offset in the Avalon 8 official specs thread (https://bitcointalksearch.org/topic/m.30730555).
It looks like the values for voltage offset enter on the CGMiner Configuration page are being ignored and the offset and some other settings are getting applied to the command line of the cgminer.  
Try entering a value there other than zero and look in Processes - at the bottom of the list you should see the cgminer command line and it always has offset of 0 hardcoded.  It looks like we can override if we use "More Options" with "--avalon8-voltage-level-offset -2" (figured that out by taking akadamson suggestion and then finding the developer documentation for cgminer on Canaan's github.

For those who don't know or are new to this, the command line options can be found here (just look for the avalon7 options and maybe the options for avalon8 will be similar):  https://github.com/Canaan-Creative/cgminer/blob/master/README

So far it is running around 80% fan speed (it was 100% before) with chip temp at 67 C.  The hash rate is staying between 10.5 -10.8TH - with the offset of 0, it was 11.2-11.5TH.
Overall it is much quieter.

I don't have a way to test the power usage so if someone else does, it would be a good thing to test.

Thanks.
Unfortunately I don't have a proper sound level meter,
but I'm estimating that the noise level is at least 65dB (as advertised at www.canaan.io) , when the cooling fan speed is 100%. Most likely 1m distance is used for the advertised noise level measurement.

Thank you and great review on the 821. Just what i was looking for.
I noticed that the fan is running at 100% all the time and was interested in the noise levels
Are you able to show the decibels these units produce.

Cheers

Geronimoe

Thanks Phil! Much appreciated. 

My one complaint is that pdf is  pretty much perfect

I sent you 7 Merit points as  it is a beautiful piece of work.