I doubt it. From memory, the ISA bus was on the bridge-board, so you won't even be able to plug the ISA cards in. Besides, ISA graphics cards are not available any more.
Hans
No, there are ISA slots on all big box amiga models, usually in line with Zorro slots. But they're passive, Amiga cannot access them. Only a bridgeboard can access these cards.
In a short answer, no you can't use any PC graphic boards on Amiga without buying extra hardware (a mediator or bridge board - even with bridge board you'ld need drivers and I doubt performance will be better than original Amiga chipset)
