If directx isn't crashing without the graphics card, it will be either a driver or graphics card issue. Try removing the nvidia driver that's currently installed (from appwiz.cpl), then installing the driver again. If that doesn't work, contact the mfr of your card to see if they want to do any further troubleshooting (like testing the memory on the card). I personally don't know of any programs that do that, but the company that made the card might.
