Thank you! on 6xRX552 - 6310 h/s, the optimal settings: { "mode" : "GPU", "worksize" : 16, "alpha" : 128, "beta" : 16, "gamma" : 8, "delta" : 8, "epsilon" : 8, "zeta" : 8, "index" : 1, "multi_hash" : 464 }