Help me pick a Motherboard

Hey guys, the last time I've been on these forums was a long time ago (probably more then two years ago) because following your advice lead me to create a spectacular machine that has really done well over the years. So +1 to all you guys out there that saw this title and thought "Hey another person that needs help, let me see what you can do." you guys are what make this forum excellent.

On to the nitty gritty, over the years I regularly upgrade/update the computer to keep it in line, starting with a 260 GTX, moving up to dual 260's, and finally I use a single 480 GTX (great card).

But my motherboard is OLD with a capital OLD.
http://www.nvidia.com/object/product_nforce_780i_sli_us.html

An nvidia 780i SLI. With 4 gb of DDR2 RAM. I have an intel Core 2 Quad Q9450 that is hooked up to a water cooling system.

This is the CPU that I think I would like (if there's a better one out there you think then I can be convinced to switch)

http://www.newegg.com/Product/Product.aspx?Item=N82E16819116901

So here is what I need:

A mother board that has the right socket and at least enough slots for four ram and three graphics cards (I'll probably never use them all but I like good air flow and not cramming cards next to the Chernobyl power plant that is the GTX 480) not to mention slots for minor cards like the old 780i.

What I would like as well

Recommendations for RAM

Recommendations for a new waterblock to fit the CPU

I still use arctic silver 5, is this still standard or is there better out there?

Requirements

My budget is as follows:

Motherboard is $350

CPU is $350

RAM is 300$ for four slots occupied and 225$ for two slots occupied

Waterblock is 100$ but I'd prefer closer to $70-80

Thermal paste is 20$

And then there is 50$ that you can throw into any of the components, ie, a better cpu or a better motherboard. But you can only use it once.

Again, overclock.net thanks for your help.