ningpra,
Onboard graphics are excellent solutions for the average user that is building on a budget and wants to jump to much higher graphics performance in a second or third step, also for the non gamer the performance off of the integrated GPU can be more than enough. Now when jumping to a separate PCI Express graphics card or cards then the world is your oyster so to speak. You can then choose the power and performance to match the games or programs your are running which are graphics intensive. As well assuming you have a PSU to support it and the space in your case then you can also look into multiple cards in either a SLi or Crossfired configuration. This is what I've just done and I'm loving life and it can be very cost effectively way to increase the usable life of your GPU performance. All of this is driven off of needs or wants and like the posted mileage on the new car sticker "Your Mileage May Vary"