extra) Testing different voltage offset values and writing down miner performance resultsNote: This extra chapter is updated in February 25, 2018.
This is a second and successful attempt to test the voltage offset values.
To get the voltage offset value working, we need to put it as a Cgminer command
in the 'More Options' field found in the Cgminer configuration page.
Here is an example: "--avalon8-voltage-level-offset -2".
See more details in screenshot images below.
The original review was done with the default setting for the voltage offset, which is
0.
I will go ahead and test the miner with every available voltage offset value.
I will let the miner run for at least
one hour and then I look at the results.
Just like with the previous AvalonMiner generation, it is possible to choose a value from -2 to +1 for the voltage offset.
Instead of changing the hash board frequency setting, AvalonMiner performance can only be controlled by changing the voltage offset value.
In the Controller Dashboard, what does the Voltage Offset option do?
We added a Voltage Offset option for users because each AvalonMiner is different with each other because of the inclusion of so many high performance chips. The AvalonMiners are very sensitive with voltage, so the “Voltage Offset” option is used for tweaking the AvalonMiner’s voltage. If the miner works well, we suggest to not change the voltage.
And, the lower voltage offset, the lower power. So if the miner works well with -2, it just means the miner has better health.
Source: https://canaan.io/question/in-the-controller-dashboard-what-does-the-voltage-offset-option-do/This time I was able to see difference in performance and power consumption value, when testing each different voltage offset value.
Power consumption was moving in about 1200 - 1300W area, and the hash rate was in 11.2 - 11.4Th/s area.
Best power efficiency results were achieved with the voltage offset value
-2.
Please notice that these power consumption results are measured power at wall,
so the power supply power efficiency also has an effect in the result.
Voltage offset value | Hash rate (Th/s) | Power consumption (W) | Power efficiency (J per Gh/s) |
-2 | 11.23 | 1195 | 0.1064 |
-1 | 11.21 | 1222 | 0.1090 |
0 | 11.36 | 1249 | 0.1099 |
+1 | 11.39 | 1295 | 0.1137 |
Cgminer status page view and Cgminer configuration page view, when the voltage offset value is -2. Click for a bigger version. Cgminer status page view and Cgminer configuration page view, when the voltage offset value is -1. Click for a bigger version. Cgminer status page view and Cgminer configuration page view, when the voltage offset value is 0. Click for a bigger version. Cgminer status page view and Cgminer configuration page view, when the voltage offset value is +1. Click for a bigger version.Power consumption measurement, when the voltage offset value is -2. Click for a bigger version.Power consumption measurement, when the voltage offset value is -1. Click for a bigger version.Power consumption measurement, when the voltage offset value is 0. Click for a bigger version.Power consumption measurement, when the voltage offset value is +1. Click for a bigger version.
Note: This
failed attempt in February 13, 2018 to test different voltage offset values was failed, because the A821 did not actually apply the voltage offset value setting set in the cgminer configuration page. After good discussions in this thread I realised that we need to add the voltage offset value manually as a cgminer command in the 'More Options' field to get it to work properly. Thanks to
lrowland21093 &
akadamson for pointing this out.
Failed attempt, February 13, 2018 - Testing different voltage offset values and writing down miner performance results
The original review was done with the default setting for the voltage offset, which is 0.
I will go ahead and test the miner with every available voltage offset value.
I will let the miner run for at least one hour and then I look at the results.
Just like with the previous AvalonMiner generation, it is possible to choose a value from -2 to +1 for the voltage offset.
Instead of changing the hash board frequency setting, AvalonMiner performance can only be controlled by changing the voltage offset value.
In the Controller Dashboard, what does the Voltage Offset option do?
We added a Voltage Offset option for users because each AvalonMiner is different with each other because of the inclusion of so many high performance chips. The AvalonMiners are very sensitive with voltage, so the “Voltage Offset” option is used for tweaking the AvalonMiner’s voltage. If the miner works well, we suggest to not change the voltage.
And, the lower voltage offset, the lower power. So if the miner works well with -2, it just means the miner has better health.
Source: https://canaan.io/question/in-the-controller-dashboard-what-does-the-voltage-offset-option-do/
I got kind of mixed results after I had tested the performance with each voltage offset value.
Changing the voltage offset value did not have such a huge effect on the AvalonMiner 821 power consumption or performance.
This is different from what we have seen with previous AvalonMiner generations.
With previous generations the highest voltage offset value has resulted the highest hash rate and highest power consumption.
And the lowest voltage offset value has resulted lowest hash rate and lowest power consumption.
Hash rate was little different with each voltage offset value, while the power consumption remained about the same all the time.
Best hashrate and efficiency results were achieved with voltage offset value -2. Voltage offset value | Hash rate (Th/s) | Power consumption (W) | Power efficiency (J per Gh/s) |
-2 | 11.50 | 1281 | 0.1114 |
-1 | 11.44 | 1278 | 0.1117 |
0 | 11.37 | 1278 | 0.1124 |
+1 | 11.38 | 1277 | 0.1122 |
Cgminer status page view and Cgminer configuration page view, when the voltage offset value is -2. Click for a bigger version.
Cgminer status page view and Cgminer configuration page view, when the voltage offset value is -1. Click for a bigger version.
Cgminer status page view and Cgminer configuration page view, when the voltage offset value is 0. Click for a bigger version.
Cgminer status page view and Cgminer configuration page view, when the voltage offset value is +1. Click for a bigger version.
Power consumption measurement, when the voltage offset value is -2. Click for a bigger version.
Power consumption measurement, when the voltage offset value is -1. Click for a bigger version.
Power consumption measurement, when the voltage offset value is 0. Click for a bigger version.
Power consumption measurement, when the voltage offset value is +1. Click for a bigger version.