Need help picking new CPU/MOBO

Ok, so currently I have an AMD triple-core @ 2.1 ghz, being read as 5.36 ghz. I wanted to upgrade my cpu, to one like this http://www.newegg.com/Product/Product.aspx?Item=N82E16819115037

I heard most games don't use 3rd or 4th cores, so I need to know if getting that cpu, with a new mobo would increase performance, and how much it would. Also If someone could reccommend me a mobo, then that would be great, that is sli compatable.

What board do you have? If its good enough, id suggest to just buy a Phenom II 720.

Well, considering for about $25 more you could have the Phenom II x4 940 BE like I do, I'd say go that route. Its a very good processor and while MOST programs out RIGHT NOW don't utilize all 4 cores, many will soon. So whatever route you go I'd say go ahead and do quad core.

http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.190729

That's a very good combo deal on the 940 and a wonderful Asus mobo