02-11-2016, 04:24 AM
Yeah, it looks like most of what you've been researching is bitcoin/litecoin mining stuff from 2011-2013. Which can be helpful, but mining is only analogous to one facet of password cracking: single-hash brute force. This is why miners can get away with ultra-low CPU and RAM requirements. Also there's an economic incentive for miners to do everything on a shoestring budget, as money spent is profit lost. But there's much more than just single hash brute force when cracking passwords, so we need things like CPU and RAM.
Currently the best GPUs for password cracking are from the Nvidia Maxwell family, i.e. GTX 970, 980, 980 Ti, and Titan X. You can go with an older used AMD card if you'd like, but they won't be as fast and they'll draw a lot more power than Nvidia Maxwell cards.
I wouldn't do more than 4 GPUs with only 16 GB of host memory. If that board only supports 16 GB of RAM, then I'd look into getting a different board.
Currently the best GPUs for password cracking are from the Nvidia Maxwell family, i.e. GTX 970, 980, 980 Ti, and Titan X. You can go with an older used AMD card if you'd like, but they won't be as fast and they'll draw a lot more power than Nvidia Maxwell cards.
I wouldn't do more than 4 GPUs with only 16 GB of host memory. If that board only supports 16 GB of RAM, then I'd look into getting a different board.