Curv,
2 things.
1) XP has a 'driver rollback' feature that might help. If the card isn't listed in the hardware profile then try doing stuff to whatever is, there must be
something listed as a video output device or the screen would stay blank. Generic VGA perhaps? Or does the motherboard you're using have an on board graphics chip it resorts to when numpties delete the registry

.
2) Reinstalling XP is a doddle compared to buying and installing a new card. You can either over-right the current install (XP will pick up and support most of your currently installed applications) or you can create a new partition on your HDD and install XP to the new drive as a fresh install, XP will happily run dual boot until you remove the old install once the new one is running fine.
