is it possible to mine cryptonight-heavy with Claymore miner ?
Try SRBMiner. For my Asus RX560 2Gb DualFan for cn/cn-v7 with Claymore - 495 h/s, with SRBMiner 515 h/s. For ch-heavy 325 h/s.
SRBMiner 1.5.0
GPU1-3 - Asus RX 560 2Gb DualFan, GPU4 - Sapphire RX 560 4gb Nitro
http://scrin.org/i/18/05/20180517200641.png