I'm following this tutorial for mining Litecoins, and I'm having a little hard time finding the optimal cgminer settings for my AMD Radeon HD 6670. Any hint on that?

The tutorial gives this configurations for Radeon 7950 series GPUs (which is not mine):

timeout /t 30
cgminer --scrypt -I 19 --thread-concurrency 21712 -o stratum+tcp://coinotron.com:3334 -u [USER] -p [PASS]
  • ¿Have you had a look at this site? en.bitcoin.it/wiki/Mining_hardware_comparison
    – Joe Pineda
    Commented Dec 31, 2013 at 12:52
  • Also, Con Kolivas descries in the SCRYPT-README an iterative process to find the optimal settings for any card, try following it and monitor carefully both the resulting hashrate (should be the highest possible) and the number of hardware errors (should be zero)
    – Joe Pineda
    Commented Dec 31, 2013 at 12:53

3 Answers 3


So far I have been using

-I 18 -g 1 -w 256 --thread-concurrency 2400

Getting ~71k/h with clock at 820 and mem at 852

I hope this helps


Ive been getting ~127kh/s with -I 19 -g 3 -w 256 --thread-concurrency 2400 Half the time Cgminer wont boot, And the room its in is around -10C with a desk fan full blast on it, And the card still reaches 50C


This is an old thread but I noticed it wasn't closed.

The previous answers are incorrect. The correct answer is:

  • None.

You shouldn't be trying to mine with a 6670. If anyone else finds this page, do NOT mine with this card. Most likely you are spending more money in electricity than you are making back.

Due to ASICs GPU mining is already being squeezed to the max and only really becomes realistic in fringe altcoin mining. But thanks to scrypt asics and god knows what else in the pipeline there is no point competing unless you have some of the top gear.

if you are dead set on wasting your time/money and burning out your old graphics card, here are the ideal settings taken from the scrypt mining hardware comparison:

  • -I 18 -g 1 -w 256 --thread-concurrency 2400

That will net you an average of 127kH/s. For comparison a top of the line card will net you an average of 1,500kH/s. Keep in mind also that not all vendors are equal, a powercolor card won't be nearly as powerful as an equivalent EVGA or XFX.

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