1. I've heard that the Slot 1, Bank 1 and Slot 1, Bank 2 would work a little faster. But u are not going to notice any difference. Maybe some really really small difference in some detailed benchmark, but nothing that u would notice without the benchmarks.
2. How to make it run cooler? Well get better cooling
. And ofcourse reducing the clock speeds would bring the heat down but no one wants to do that.
3. It's nice.