That's the memory on the graphic card. Totally independent of the RAM on your motherboard.
You've got to be sure, however, that the card itself fits. That depends on the slot. There's:
- AGP (old)
- PCI (newer)
- PCI-E or PCI-Express (latest)
Hope this helps.
I have a GeForce 7300le, i am thinking about upgrading to an 8600 or 8800 card, but the spec on the new cards says the memory amount is 256MB GDDR3, what does the GDDR3 mean? will it fit into my motherboard?