i had 480 sli i like my 580 more, No sli issues only thing is the i7 930 is power hungry when overclocked. so are the 480s , my i7 930 @ 4.2 and 480s overclocked and power down the fan on my old 750tx ran for 5 mins after shut down.
best thing is ssd, new cpus coming out to lower the power output/heat of the cpu, and as other said 480 in tri sli is fast but memery limited. mite want some 7970 xfire or titan to be faster but titan is $$$$ i would wait and see what the next gpus can do, the new cpus are in june, but the i7 930 is still powerful.just power hungry.
Mite need a good mouse or mech keyboard, i love my yotd reds (keyboard) , or a game pad, like te n52 or g13 (i like the n52 te but died (lifetime warranty).
But fast ssd are NICE, MIte want to fill out system specs so we can help more