And compared to a 1080 ti rig 4k is no problem Id get two of theese then with a much higher hash!
But will wait and see that it actualy works out for people first. Too big a investment to just go for it as it will be hard to sell it if i cant use the fpga.
But happy that the OP will actualy give out the necessary code
FPGAs retain their value very well and hobbyist are always on the lookout for them on eBay. If it does not workout for you, I will be here ready to collect.
You can also learn a lot from the code below if you are into this kind of thing, it is very easy to follow and has temperature monitoring capabilities.
https://github.com/0x2fed/FPGA-Keccak-Miner
https://raw.githubusercontent.com/0x2fed/FPGA-Keccak-Miner/master/nopll_v3/v3.bmp