In most cases, do not worry about disabling the onboard video just yet. Install your new graphics card in the the slot and put the case back together. Attach the monitor cable to the new card and boot the machine. Windows will load a default driver to give you a picture. Windows will then give you a pop up that says it found new hardware. Cancel this operation and all others that pop up. Open your cd/dvd and insert the driver/software disc that came with the card. Run the cards program and let it install it's own drivers. When it is done, remove the disc and reboot. The computer will now go to the new graphics card and ignore the integrated. I never uninstall the integrated because stuff happens and if something happens to the new card, you have something to fall back on in case.