Im building a PC mainly for games. I am getting the lntel core 2 extreme proccessor running at 2.93.ghz, 2GB ddr 2 ram 800mhz and a CAS latency of 5-5-5-12. Im having difficulty on deciding what video card set up I should get. I get mixed answers when I ask what performs best a single card or a SLI setup. Im looking at the 7900GTX 512mb. Im told that a SLI setup causes alot of overhead and I would lose most or all of the performance that the SLI setup would give. I do have another concern about the computer im building. A CAS latency of 5 is kinda high from what im used to. When I had DDR1 The highest CAS latency I had was 2.5. Will this affect performance much or at all?