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Is it worth going SLi, if you have the money obviously. Are the performance increases cost effective etc.
Actually SLI isn't the waste of money most people of these forums say it is. For what it's designed for, (i.e. increasing minimum framerates and turning all the eye candy up) it's actually very good especially with the more demanding titles. Older games give less of a benefit but all of the 30% at most nonsense is from those who've never tried it tbh. I had good results with 6800, 7800 and 7950 SLI systems and they're great once you've set them up correctly. Considering the other (mostly) pointless stuff people waste money on for gaming systems (RAID arrays, QX cpu's etc) I don't see it as a waste even at 1600x1200, you just get more aa/af. Considering a lot of people build their machines mainly for gaming I can't see anything else you could spend the money on that would even come close to providing a smoother gaming experience.