HP a6554f - Asus IPIBL LB: Graphic Card Solution

First of all, sorry for me english and thanks in advance for your time

Well my graphic card die after 3 years of intense gaming   (9800GT)

This is my PC:

HP a6554f
Q6600
Asus IPIBL LB
Antec 600w
5GB of Ram
Windows Vista 64bits

I want to buy something for 130dlls(all my money) from here:

http://www.frys.com/template/index/

or

www.bestbuy.com

NOTE: Im from Tijuana(in the border with California) so i guess i only have two ways to buy it: Fry's and Best Buy

But well my real problem is my case/motherboard, i dont know if i can run a graphic card with two slots(wide?) like the GTS450...

Because if not...9800gt is my best option?