I do not understand why you could not just use the internal memory located inside the FPGA. Many new 16nm Fpga has upwards of 75 megabyte of memory. I would think having 37 really fast cores would be better than trying to use slow external ram.
Anyways, I found a reddit post of someone who supposedly did 20 kh/s on an monero FPGA miner. https://www.reddit.com/r/MoneroMining/comments/7s9zwe/fpga_mining/
Could you give a link to the XMR V7 discussion?
It is true about internal memory, yes, tens of megabytes and dozens of cores. But what is the overall hashrate of the solution using internal memory? Data dependancy and high latency make memory stalled almost all the time. I suppose the external memory would hide the latency of AES and multiplier.
Anyway the practice is the cretery of truth. If 20KH/s miner is possible - OK, lets build it. I have not done the IP core of XMR yet, so my estimations are rough and careful.
So I do not change my answer - top 16 nm FPGA and dual-triple coin minning in mind is reasonable choice for miner.
I have to find the the link, it is somewhere in browser history.
I found a website that sells Boards with multiple FPGA’s on them (http://www.dinigroup.com/web/index.php)
If you want to work on the dual/triple Miner with me, I have the code to a NIST5 miner.
Kinda currious where did you get 10 mill gpus would really like to see if someone did the math on that one 
