You seem to have pretty much covered what I would do.
You could try uninstalling any software related to the card, remove card reboot. Then do a system restore to before the card was installed.
Note though that this will also remove any other drivers and programs you have installed since that date. I have found it best to uninstall any programs that fall into this category before doing the roll back.
Once the system is restored clear out all the temp files, if you have Norton Systemworks run Norton Win Doctor to remove registry entries.
Then install your card.