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#11
From what I know, There shouldn't be a compatability issue, but in special cases there may be one. But as I don't know, I cannot comment on it. Perhaps a way to find out is if you have a spare (somewhat similar) card that worked for your motherboard. But don't go out and buy anything. 600watts power supply is fine for what you got.
I'm not sure I really know whats going on with your stuff man. Maybe it is compatability issues after all. Have you looked all throughout the BIOS for anything and EVERYTHING that has to do with pcie and agp? check for multiple locations.
I think I've come to the end of my knowledge in this area. Perhaps someone else may know a bit more specific to your problem, as your board is a little older and I've only studied a bit on the newer stuff. sorry mate