Ethash mining is not memory bound. It has, if I remember correctly, a precomputed buffer used by many operations. To quote Wikipedia: "Ethash uses an initial 1

Ethash mining is not memory bound. It has, if I remember correctly, a precomputed buffer used by many operations. To quote Wikipedia: "Ethash uses an initial 1 GB dataset known as the Ethash DAG and a 16 MB cache for light clients to hold. These are regenerated every 30,000 blocks, known as an epoch." You generate it once, access many times. If each memory access is 32-bytes, then one need not more than 32*2^20 computations to get completely sequential access. To very probably not miss a prefetched DRAM block (main throughput bottleneck), which is 4K..8K in typical size, one need about 128 times as less computation threads. And this number (~250 thousands threads) is well within reach for current GPU models. State of the NN weights will change after each batch, on the other hand.