I have a FIC VT-503 motherboard. It is a late 1997 vintage 430tx motherboard.

It currently has a Trident video card installed. The card is a a 5-volt 32-bit unit with a single key towards the rear of the card edge connector.

I have 2 TNT2 M64 cards both of them are universal 3.3/5 volt units, with two keys creating three sections of card edge, a large middle portion and two equal size border portions.

The TNT2 M64 cards will not work in my motherboard no matter what, but they will work in my PIII system. I've tried different power supplies and processors, nothing makes a difference.

Why won't these cards work?

Do I need to stick with 5-volt 32-bit cards? If so, what should I be looking for?