Why the lack of love for AMD? The new X2 64 processers are the best yet and as stable as any Intel I have used.
I love my AMD processers and am using one now, and they overclock so much easier and are more stable then Intel when you do. As for mobo I'd have a look at ASUS if you don't mind changing CPUs from Intel to AMD and keeping to nVidia. My board cost me just under £100 and is very good for the money, AI overclocking, network management, SLI ready, and DX10 ready. Ask if you want full specs of the board but you can always Google it, its the one in my signature. That whole rig only cost me £650 not including monitor so shop around online and see what the best prices are you can get.