Check the manual on the motherboard, it recommends setting a jumper for the voltage on your agp bus. Try the solution listed in "Example 1:" on the 1st page. This happens a lot with agp 8 cards Ive found, since the card tries to negotiate its speed with the agp bus, since your MB doesnt support AGP 2x, but the card does, I'd suspect thats part of your problemo. Let me know...

link to manual:

http://america.giga-byte.com/MotherB...n400pro2_e.pdf