Question 1: What resolution do you play at? Unless your on a huge monitor, (1680x1050 and up) dual GPU doesnt really pay off. Infact at 1680x1050 I would just get a 4870 1GB and enjoy. You only really need more at higher rez.
Ill probably just add on another 4830 then, or just go with replacing the 4830 with a 4870 1gb. Considering the 4830 is all I have.
I'm only going for 3.1ghz because I'm playing it safe and I'm not gonna go extreme with the oc. I dont want to risk any trouble at all. I might go for higher once I get an aftermarket cooler this summer.