I have a feeling you are going to have a miserable time with any meshes subdivided more then then a very fewer layers. ZB is really hard on graphics cards and especially graphics cards memory.

But you can generally find out some details on your integrated card by right clicking on the system icon going to properties then hardware then device manager and look for the display adapters.

If you decide to replace the card with an AGP or whatever your mobos graphics connector is be sure to go into the bios setup and turn off the integrated adapter and make the one in the card slot the primary video adapter.

GL