If you’ve not started mining luxcoin yet, go read my guide on getting started first.
Luxcoin is the coin to be mining right now. Rather luckily for those of us in the know, whattomine.com has not listed the phi algorithm on it’s homepage. What that means is the general public who have not heard about mining lux on their own channels don’t know about it. That means less miners, which means less difficulty, which means more profit for those of us with an ear to the ground.
There is one drawback to a coin with a lower volume of miners- there are less people figuring out how to mine it, and how to mine it well. And so it appears the task has fallen to me.
Please read the whole article before making any changes to your config file, as I found some settings actually stopped some rigs working even when the changes were rolled back.
I spent many hours figuring this out. Tips small or large are welcome, my address for LUX is LMMLQvz3ZZo6R29vZM7gCgBQUsvyGYChjh.
Note that this information is for RX580 8GB cards. I did however see good improvements using these settings on a rig with RX480 4GB cards. I therefore think this information is valid for all AMD RX series cards.
The speeds i acquired with these changes are:
RX580 8GB – 17Mhs
RX480 8GB – 16Mhs (@ Stock, probably can go faster with overclock)
RX480 4GB – 15.5Mhs (@ Stock, probably can go faster with overclock)
This information is for SG Miner 5.6.1 and may not still be valid with new miners in the future.
Drivers & System Specs:
Drivers seems like less of an issue than with most other miners. I had been using the AMD blockchain drivers, but noticed that using AMDs latest drivers instead (17.12.1 at time of writing) made no difference at all. Therefore I think you can use whatever the latest standard package is without drawback. Edit: With the new drivers on some rigs i’m having problems GPU 0 running slow. It may be best to stick with the blockchain drivers.
I also noticed that in general system RAM quantity is important when mining LUX. Systems with more RAM perform better.
Config File Variables:
So, without further ado, let’s look at the commands one can add to the config file. I’ll detail all the commands I tried, and their results.
Note that all tests were done at -i20. I did test alternative I settings, but they resulted in lowered performance averages.
––shaders <value> Screwing with this made no notable difference.
-nfactor <value> The default value of 10 seems about right. I tried various settings, which all just seemed to make the hashrates jump around a lot. Leave this alone or set it to 10.
––worksize <value> Changing this does make some difference. It also seemed to make the values much more dynamic over time. I settled on a value of 128 as that seemed to give a stable and high result.
––thread-concurrency <value> Now we are into territory that makes a difference. A RX580 card has 2304 shaders, so you need to use a multiple of this number. I tried most values, but eventually settled on 4608 has giving the best result over a longer period of time.
––gpu-threads <value> This value is the big daddy, the one that will really make a difference. However, setting it too high will result in an error or a crash to desktop. As far as I can tell the value you can use is linked to your GPU & system RAM. More RAM means more threads, but i’m not totally certain what the link is yet. I found on some of my rigs with just 2GB of RAM, that after putting this setting in, they would crash to desktop and continue to crash to desktop even after the setting was removed. This was fixed by creating a new user in windows and trying again with a roll-backed config. At least one of my rigs with 2GB of system RAM did allow 4 threads on 4GB cards, but not 8GB cards. So try various values and see what the highest value you can use is. I found 8 is the maximum and gave the best performance. The higher number you can use, the better performance will be.
The Ideal Config
You can download a BAT file with this config typed in for you here.
Given all of the above, the best config I have found is (If you copy and paste this, check the dashes stayed as short dashes):
setx GPU_FORCE_64BIT_PTR 0
setx GPU_MAX_HEAP_SIZE 100
setx GPU_USE_SYNC_OBJECTS 1
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_SINGLE_ALLOC_PERCENT 100
sgminer.exe -k phi -o stratum+tcp://eu1.altminer.net:6667 -u LMMLQvz3ZZo6R29vZM7gCgBQUsvyGYChjh -p c=LUX -I 20 ––gpu-platform 2 >log.txt -w 128 ––thread-concurrency 4608 ––gpu-threads 8 ––nfactor 10
Overclocking with LUX mining will let you squeeze out those last few hashes. Lux is much more sensitive to core speeds, and I found I could push my RX580s up to 1475MHz without getting unstable. Memory speeds seem to make less difference, but it did slow down a little with them reduced so i’ve left them at 2200MHz. I’ve not tried BIOS modifications at all, as I like my warranties. However i’m sure with some modification it may be possible to squeeze out more.
That’s all. Good luck! Please leave your results and system specs in the comments below, as more information over more rig variables will help me to perfect this further.