Does the motheboard have more than one pci-e slot? no matter 8x speed or 4x speed...if the graphics card went...it might have taken the slot the gpu fits in as well OR maybe the slot failed and the card is still good!!
Either way...move the video card to another slot and see if the motherboard will boot...but you didn't mention if the graphics card you are trying to use is the same make...nvidia or ati...as the card you said went bad...if it's not...say you had an ati and am now trying to install an nvidia card...you need the drivers for the make of card you are trying to install.
You didn't say what O/S you are using windows xp...vista...win7...64 bit OR 32bit...or even if you are using ubuntu...linux...opensuse..etc....all make a difference in how the video card driver is installed and if any default drivers are available for windows drvstore...
Sorry for so technical...but some of if not all of that information is relevant to what you are attempting.
It's a simple thing to swap out a video card...but as in all things...it all depends on what you are working with!
Check a different slot First...AND you should clear the cmos so the bios will recheck the hardware and "discover" the new video card...sometimes it doesn't do this during POST and you wind up with a black screen!
Clearing the cmos means REMOVE ALL POWER from the computer...remove the battery on the motherboard...short or jumper the pins to CLR CMOS. then put the jumper back to it's original position and reseat the battery...then plug the power cord back up and begin the boot...during POST the system will rediscover all hardware including the NEW video card and should allow the generic drivers to be loaded up by the O/S.
give it a try and read up on the internet concerning your board...also your manual should help you perform these steps.
Good luck
