@cmichael138 thanks for your reply. my psu brand is rich tech 450 w. and one more thing when i start using the graphics card the monitor sometimes starts but in the middle some lines start coming and the monitor goes blank. But with the on board graphics everything is fine. Pls reply immediately i need help urgently. One more thing is my 450 w power supply enough for my hd4350 if ti may be the problem.