So I have two Antminer S9's, both are 11.85Th versions.

Now one uses V4 hashing boards and the other uses V5 hashing boards. Both of them have a hashing board missing each (the hashing boards failed and I sold them on Ebay).

Now I want to create one 'complete' miner again and want to know if there's a way to put three working hashing boards together in a miner (say two V4's and one V5).

Now I've tried just slotting them in and no luck, but wondered if there was something I could do with the firmware to address this? This is where my 'expertise' finishes sadly.