SLI Mode lets you run two graphics cards together.
You can not use a GeForce 7600GS and any model from the GeForce 7300 series together in SLI Mode. The reason why they won't work together is that they each feature a different Graphics Processing Unit (GPU).
GPU
All graphics cards in an SLI Mode array need to have the same GPU In order for SLI Mode to work. Some later models of the GeForce graphics card family use three-digit and four-digit identification numbers while using the same GPU for both, creating some crossover. However, Nvidia did not do this during manufacture of the GeForce 7 series, so all GPU models have the same number.
GT, GS, LE, SE, Etc.
Originally, you needed to have the same model version (GT, GS, LE, SE) to get SLI Mode to work. However, Nvidia has patched their software and you can run different versions of the same model in SLI mode with the updated software.
Brands
The brand names do not need to match in SLI Mode. You can run PNY and BFG cards together in SLI Mode as long as they are the same model number.
Tags: have same, same model, cards together, graphics cards, However Nvidia