Really hoping somone may have done an upgrade to their FX 540S to help me out on this, or someone who can tell me exactly where to connect the additional power source to on the computer side.. Doing a graphics card upgrade for my Gateway FX 540S, from the existing Nvidia GeForce 8600 GS to a GTX 660. I cannot figure out where to get the additional power source on the computer side to go to the 6 pin card port. Done a lot of research without any results. There are some vacant connectors in the case, couple of vacant six pins on one end, and a vacant plugin connector near the card. I also found some info that said you can't change the existing card out on this Gateway model. Nvidia support said it will work, I just don't know where to connect the additional PS connectors. Thought this upgrade was a slam dunk, just don't want to connect it up wrong and fry something. Appreciate any help.