I bought an Asus G74sx-bbk7 from Best Buy. The video card should be running with a 192-bit memory bus width, but mine only has 128 bits. Is there any way to "unlock" the other 64 bits?

This is NOT a 560 Ti, it is the 560m for laptops.

I understand the danger of unlocking a video card and I know that any damage to my computer is purely my fault. I'm just curious if there is any way to get my card to use it's full potential.