Im trying to build my first computer, and I settled on this as my graphics card, however, the GeForce GTX 460 (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card version is sold out, and I was wondering if there much of a difference between that one, and the 768 MB, 196-bit version. They are only 20 dollars cheaper, so Im wondering what the difference is. Any input would be appreciated.