Re: Claymore's Dual Ethereum AMD+NVIDIA GPU Miner v15.0 (Windows/Linux)
How fix? : "not enough GPU memory to place DAG, you cannot mine this coin with this GPU , cannot allocate big buffer for DAG" 
Same for me :
ETH: GPU0 0.000 Mh/s, GPU1 0.000 Mh/s, GPU2 0.000 Mh/s, GPU3 0.000 Mh/s, GPU4 0.000 Mh/s, GPU5 0.000 Mh/s
GPU 0 failed
Setting DAG epoch #352 for GPU0
GPU0, OpenCL error -38 - cannot write buffer for DAG
Setting DAG epoch #352 for GPU4
GPU4, OpenCL error -38 - cannot write buffer for DAG
RX570 4G under linux (ethos)