Well it should be possible, but running Snow Leopard is difficult on AMD (even more than running old Leopard), due to the lack of a Kernel that automatically patches your binaries but if you want to have proper use of your gfx card (including dual monitoring) Snow Leopard is the only choice.

I higly recommend you to put some money into a qualitative, stable mainboard with Intel chipset and an Intel CPU, if you are looking into using it as a productive setup.

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