Build Question

[jhammock85]

I am looking at getting a Phenom II set up. I already have a few things, but I am not sure of the motherboard.

Here is the processor I am looking at:
Amazon.com: Phenom II X4 965 Black AM3 3.4Ghz 512KB 45NM 125W 4000MHZ: Electronics

Also, I currently have 2 of these:
Newegg.com - EVGA 512-P3-N862-AR GeForce 9600GT Superclocked 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card

My question is first, am I going to see a huge increase in quality of graphics and efficiency if I switch from 2 9600GT to 1 Radeon 6850?

If so, I would like to know what is a basic motherboard for the processor? If not, I would still like to know what is a good motherboard, but I would need something with 2 PCI Express slots to enable SLI.

Thanks in advance.