K , so i configured a system on newegg but i am having some second thoughts and was thinking i would like to get a second opinion.     Below are the specs:
AMD Phenom II X2 555 Black ed.
ASUS mobo
Wintec Gaming Ram
Nvidia GTX 450

I already have Hdd, Case, PSU, Monitor, etc...

However, i am seriously thinking about going over my $400 cap and buy the new GTX 560 Ti vs. the GTX 450.

Thanks for help you guys, and happy gaming!

I have the Phenom II x4 955 BE 3.2(oc'd to 3. 4gb RAM DDR2 800 and a GTS 250.  

Havent found a game i cant max out at 1920x1080.

Anyway, i mean if you have the money, i say go big or go home.

Here is a list of LOTS of cards, compared stats wise.  I believe it goes from 'weakest' to 'strongest'.  Hopefully that helps.
http://www.hardwaresecrets.com/article/132

I would go with a 4 core or 6 core if your going to spend a little more. Must of the new game run better with 3 or more core. I updated to a 6 core AMD a month ago I'm still using a GTX 275 and it runs Black ops at Max setting at around 100 FPS. My old 2 core, I had everything on low and still was getting 50 FPS or less.
Stingray

I could be wrong but unless the games are written to take advantage of mutliple cores having more than say 2 wont matter.

well... i know that 4-6 cores are great but i have heard that with the black ed. cpus you can possibly unlock the dormant cores, however that means i would only be able to overclock two core instead of all four.

u can only unlock the cores if there not bad and if i remember right your board needs to have a SB 750 or better