I am using this miner... Got some luck and found a block in just a few hours.

1 and 2 - 7850 1gb
3 - 6970
4 - r9 280x


[1] 1.047G, average: 1.004G
[2] 1.030G, average: 0.985G
[3] 0.635G, average: 0.650G
[4] 2.082G, average: 2.045G
 * speed: 4.795G, average: 4.684G
   * chains/1: 699918733 43674.145/sec
   * chains/2: 53152864 3316.679/sec
   * chains/3: 6155896 384.121/sec
   * chains/4: 481788 30.063/sec
   * chains/5: 37850 2.362/sec
   * chains/6: 2909 0.182/sec
   * chains/7: 225 0.014/sec 50.543/hour
   * chains/8: 15 0.001/sec 3.370/hour
   * chains/9: 1 0.000/sec 0.225/hour
   * chains/10: 1 0.000/sec 0.225/hour