The time has come for me to retire my system that I originally built in 2002.  I've upgraded the RAM, the graphics card but the board and CPU have stayed the same.  I've come to find out that CoD4 won't support my Athlon XP 3000+    so it's time to build a new one from the ground up.  Basically I'm trying to build a computer that will allow me to play the latest games (which is what I use my comp for mostly), not necessarily at the highest settings but will be able to be upgraded in the future.  I went out and got a killer deal for an 8800 GTX and figured I'd get a value RAM in meantime to off set the cost and get some premium stuff later.  I don't wanna overclock my stuff, I've had some bad experiences with it.
 
I've got a couple pieces so far and I'm looking to put the finishing touches on it this week.  What I have so far is:
 
Antec P182 Special Edition Tower
Antec TruePower Trio 650-Watt Power Supply
Creative Sound Blaster X-Fi Xtreme Gamer Sound Card
GeForce 8800 GTX
 
Now here come the questions...
Will that power supply be able to handle two 8800 GTXs?  I plan to eventually get two and changing out a new power supply doesn't sound fun.
 
I can't decide between processors, either the Core2Duo 6750 or the 6850.  Is there really that much difference between the two to warrent paying $80-$100 more for the 6850?
 
As far as motherboards go, I usually go with Asus but I've been out of the loop for so long I have no clue about them.
 
And finally RAM, it used to be to easy to figure out which is the best.  I'm looking for value and will upgrade later.  I've heard Kingston works pretty well and A-data was also a good value buy.  Any thoughts?  I'm going to go with 4G to work with Vista and again I'm completely clueless to which RAM would be best.
 
Any help would be awesome, thanks in advance.

1. probably not at least Pc&c 750 quad for dual gtxes.
2. E6750 can oc just as high as e6850.
3. Crucial Ballstix 800mhz 4-4-4-12

8800 GTX SLI can use a lot of wattage. The single card pc would need 500W 34A on +12V combined. The SLI qualified psu for GTX SLI goes from 750W & upward. So that is a safe bet.
 
Well, you're not gonna o/c due to bad experiences. So I'm not gonna talk you into it. Get the e6750 if you can't afford the e6850 which is the best gaming cpu for now.
 
As for ram, same thing, no o/c. Get something like this:
 
http://www.clubit.com/product_deta [...] FC-CJ_CBIT
 
As far as mobo, how about ASUS P5K?
 
BTW, this case is nearly half price after rebate & can hold 2 8800 gtx:
 
http://www.clubit.com/product_deta [...] FC-CJ_CBIT

nice....