Had similar problem with almost identical hardware: replaced DualCore cpu with QuadCore, Foxconn G41mxe board, AMD5770, 500W psu & system would not post. Solved by resetting CMOS(instructions in motherboard manual) - worked perfectly thereafter...
Already tried it!fukn nothing!!thanks anyway,ill just take it in to compuport,and to go wiht that my fukn hdd burnt out!!my friends hdd also burnt out!!?but their both on warranty so we'll get new ones and try again!