Check that the card is seated properly. Go into 'Run' on the start menu, type cmd. Into the prompt type the following:
set DEVMGR_SHOW_DETAILS=1 (enter)
set DEVMGR_SHOW_NONPRESENT_DEVICES=1 (enter)
start devmgmt.msc (enter)
Device manager will launch. Look into 'Display', 'System Devices' and 'Non Plug-and-play' devices and see if you see your card listed but greyed out. Look for which items are greyed out.
Have you downloaded and installed the Chipset drivers for your board (32 or 64 bit?) Do that also if you havent.