Well you have a 1.0 mobo, so i would stay away from 2.1 cards.
The 4350, being a 2.0 card, should work with your mobo. But i heard a moderator say amd came up with the 2.1 numbers because of compatibility problems with other cards, so i'm not completely sure it will work. What high end cards you tried before ?
You remember who stated it will work ?