Will i see a difference in running a GTX 550 in a pci express x16 vs a pci express 2.0 x16 slot?

i already have a gtx 550 and i just realized i’m probably not using the card to it’s fullest potential. i was really wondering if making the jump from pci.e x16 to pci.e 2.0 x16 is really worth it for me. it would only be around 70$ for the motherboard i’m looking into. http://bit.ly/pY9rvn