i wish it was passive, but there are a pair of chips common on the g-rex, bvision and cvision cards:-
Cypress Semiconductor CY7C375I-83AC, and CY7C374I-83AC
apparently these are both 128cell macrocell flash CPLD's - so i suspect they are responsible for completing a lot of the PCI glue logic. they certainly get hot enough!
i have no idea on CPLD programming or reading configs, so looking at it, you'd need to pull the config out of these chips and implement your own version...
I'd ditch my mediator, and put my CS-Mk3 in my A4k in a heart beat for a g-rex or equivalent though....
