Perhaps if you were to ask the previous owner they'll be able to tell you?
Failing which, if you can post a few photos of the actual card (use click here to host the photos, & post the links here), one of us may be able to tell you the type of interface: PCI, AGP or PCI-E.
Also, let us know the type of graphics card your motherboard is compatible with (or the motherboard's make+model - use SIW click here if necessary).
With the above info, we may be able to determine if it's OK to try out. G