eh. well....you may or may Not see a marked improvement in the display with a vidcard upgrade. the new card is mainly for new visual effects that the chip may not have handled, but more importantly, it takes some of the load off the processor as cards are dedicated to video rendering.
so you should be noticing less lag and faster screen loads, but prolly not better image, alot of that has to do with your monitor and Not the card.
somthing to check though is to see if they bothered to Disable the onboard chip.
Control Panel ->System->Device Manager->Display Adapters.
thattl show you what is currently running the video on your comp.
if its not the card you bought, they didnt disable the chip, and you can do that (hopefully) from the system BIOS on boot.
~Syn