Finding Optimal Litecoin Mining Settings

Tuning your Litecoin mining system to get ideal performance can be a royal pain in the rear -- this I know from personal experience. Settings that work great for one person can end up being terrible for another individual. So if you've just bought a shiny new Radeon R9 290 or R9 290X (or any other GPU for that matter) and you're trying to get better hash rates, here's the general plan of attack for getting optimal mining performance from your system:

1. Ideally you want to mine at intensity 20, as that will result in the fastest performance, but the system will not really be usable for other work.
2. Start at reasonable settings and then start increasing GPU clocks and memory clocks until your system becomes unstable.
3. You'll probably need to play with fan speeds and/or voltages in the process of tuning.
4. Once you've found the clocks that your GPU will handle, start looking for the optimal thread concurrency setting.

Needless to say, dialing things in can take days if not weeks, and every crash and restart can be maddening. I'm trying to build a set of batch files to automate things under Windows. Here's what I have so far, for finding an optimal thread concurrency setting. You need to put the two batch files in your CGminer folder, without any active cgminer.conf file.

ThreadConcurrency.bat:

@echo off
set threadconcurrency=18000
:startloop
echo Current TC is %threadconcurrency%
start /wait "MinerThread" miner-tc.bat %threadconcurrency%
<nul set /p =%threadconcurrency%:  >> AvgHashrateTC.txt
type %threadconcurrency%.txt  | find /i "average hashrate" >> AvgHashrateTC.txt
set /a threadconcurrency=threadconcurrency+64
goto :startloop


miner-tc.bat:

@echo off
set threadconcurrency=%1
cgminer --scrypt -o stratum+tcp://coinotron.com:3334 --shares 5  -u trogdorjw73.tester -p tester -w 256 -v 1 -I 20 -g 1 -T --gpu-engine 965 --gpu-fan 70 --gpu-memclock 1550 --gpu-vddc 1.075 --temp-target 85 --temp-overheat 95 --temp-cutoff 99 --thread-concurrency %threadconcurrency% > %threadconcurrency%.txt
exit


Place those two files into your cgminer folder and then run ThreadConcurrency.bat (tweaking as needed for your mining pool, temps, etc.) and walk away. Your PC will run through five shares at each thread concurrency setting and spit out the result to a file called "AvgHashrateTC.txt", and you can look at that in the morning after running the batch file all night (or in the evening after running it all day if you prefer).

There's a catch, of course: I set the above to do five shares, and sometimes you'll get lucky or unlucky so hash rates can be higher/lower. Setting the shares value higher (like 20 or 30) would take longer to get through a sequence but it would be more accurate. When you're fine tuning that's worth a look, and maybe you could even change the increment from "+64" to "+32" or "+16" -- or even "+1" if you think that might help.

You can use the same approach for clock speeds as well, but you'll probably want a maximum clock (or just let it go until your PC reboots). I'll post some batch files for that tomorrow. Also note that on the R9 290/290X cards under Windows, when cgminer exits it often causes a BSOD -- no fun! I'm not sure if that's drivers or cgminer 3.7.2; I need to try poking around a bit, but it's a real irritant. Closing the window with the X in the corner avoids the problem, but that doesn't work with CGWatcher or my batch files above.

If you find this useful, go ahead and run the files as above and I'll get a few mining shares during your testing. Optionally, feel free to donate to my blogging efforts by shopping online or via LTC donations. Or win some for free and give me a commission.

LTC: LXpEZcNJtikd263z7Ha3vrdYDcLU7hiKWv