I've been lookin' around and have yet to find the answer to these questions.....
1. Do you need to have an ATI chipset on your MoBo if you plan to use an ATI video card?

2. AGP or PCIe? I have heard that the AGP is being phased out, but my source for this info is more than a little unreliable.

I would like to thank you all in advance. I am just gettin' started with PC building and it's a lot more involved than I thought.

Yes, AGP is definitely being phased out, although it is far from dead. I read somewhere that it still holds 60% (?) or more of the video card market right now.

I would recommend going to a PCI Express system, however. On Newegg at least, the prices are lower, and you'll also get a larger selection of mobos and video cards. Not to mention it's higher bandwidth and clock speed.

No, you don't need to match the brand names together. ATI has just barely got into the mobo chipset market, and while they are full-featured, they still have some bugs and don't perform as good as nVidias chipsets.

My mobo recommendations:

nForce 4 (nVidia): DFI Lanparty UT NF4 Ultra-D, or SLI-D (for overclocking), ASUS A8N-SLI Deluxe (for stock speed, and ease of use)

ATI Xpress 200: ASUS A8R-MVP (great price, has Crossfire, overclocks as good as DFI boards).

pfffft Ator, you just beat me to it -.-
I built my brother a computer with an ATi chipset and Nvidia 6600GT. Works great.

AGP is slowly being phased out. However, not everyone can afford to upgrade to a new computer on the spur of the moment. Case in point, I'm still running an AGP graphics card I believe that is the reason why AGP still holds a command of the video card market right now. I will in fact upgrade to PCI-e when I build a new computer :-D

Quote: My mobo recommendations: nForce 4 (nVidia): DFI Lanparty UT NF4 Ultra-D, or SLI-D (for overclocking), ASUS A8N-SLI Deluxe (for stock speed, and ease of use)

Ator , I agree with you on everything but the point about the Asus and overclocking.
I do wish it had more memory tweaks ,but ive never had a single problem Oc'ing with this board.

I think the New Dfi lanpartyboards are great ,but most people are lost and completely overwhelmed by the plethora of options available.
That said ,I'll Also be useing a Dfi board in my next build.
I love methodically adjusting and testing everything to see what changes,and how far you can push things.

Hmmm thanks for the advice, this gives me some food for thought. I might have to rethink some components. I'm completely a noob as far as OC'ing goes, but I'd rather spend a little extra money getting components that I will get the most use out of down the road.
I think I'l' take all the advice you guys have thrown my way and pick up a DFI board. Then you guys can laugh at my noobness at tweaking. If there was one thing that I learned in my years in the Navy, it was that you can teach anybody to do anything (as long as you have a big enough hammer).