Here is a quote from github on Scypt's massive memory requirements. By Jsteube.
- "GPU's will not be able to crack this because of the memory requirement. Math behind: Mem per candidate: size_scrypt = (128 * scrypt_r) * scrypt_N = 256MB. But to make use of the GPU power, we need to spawn at least 1280 parallel computations, so we end up with a memory requirement of 320GB ram per GPU. It would require a minimum of a 256 divisions TMTO to get it working on a GTX1080, which drops the performance < 1 H/s."