If the problem is specific to certain old programs then sure try running them in compatibility mode, it's definitely worth trying.
And a video card or any hardware can cause issues if there are physical defects or improper drivers; so replacing the card sounds extreme unless it is damaged but definitely make sure you are running the latest drivers for it.
Gigabyte GeForce 460 is W7 compatible according to Microsoft.
Since you say it happens with digital audio software I would also look at your sound drivers (make sure they are the latest) and look at the codecs you have installed (maybe uninstall some and see if the problem persists).