This is my pc:

E8400 3Ghz @ 3.25Ghz

ASUS P5QL-EM

2GB RAM Kingston 800mhz

PSU 450W 12v has 26Amp

and i want to buy a graphic card. I looked this:

ATI HD4670 1GB

GeForce 9600GT 521Mb

my question is: would any of those run with my PSU?

is there a lot of difference between the 800mhz and the 1066mhz memory?

E7400
Msi P45 Neo-f
2gb 1066mhz Ocz Platinum
Xfx Geforce 250gts 512mb Core Edition 256-Bit Gddr3

or

Q6600 Core2quad 2.4 8mb
Msi P45 Neo-f
2GB 800MHZ KINGSTON
Xfx Geforce 250gts 512mb Core Edition 256-Bit Gddr3

???

wich is better for games?

is there anything that will limit the capacity of the computer?

E7400
Msi P45 Neo-f
2gb 1066mhz Ocz Platinum
Xfx Geforce 250gts 512mb Core Edition 256-Bit Gddr3

or

Q6600 Core2quad 2.4 8mb
Msi P45 Neo-f
2GB 800MHZ KINGSTON
Xfx Geforce 250gts 512mb Core Edition 256-Bit Gddr3

???

wich is better for games?

is there anything that will limit the capacity of the computer?