SH3 GWX Computer Upgrade Question/Suggestions

[Checkmate King 2]

I want to upgrade my computer mainly for playing SH3 w/GWX & IL-2 1946.

I'm currently running 1 gig of memory (2X 512mb) however, my video card is an integrated NVIDIA GeForce 6150 LE Graphics with up to 256MB shared video memory.

I plan on getting 2X1 Gig memory cards.

My big problem is what type of video card to get.

Below is my specs for my computer:

http://h10025.www1.hp.com/ewfrf/wc/d...Url=true&#N407

This is the specs on my power supply:

AC input voltage (47-63Hz):

100-127V/8A
200-240V/4A

DC output wattage: 300W

Dimensions: 150mm x 140mm x 86mm


I have an Asus motherboard


I would like to order from either Amazon.com, Newegg.com, or Tigerdirect.com.

I know I cannot get a top of the line video card due to my 300w output.

Any suggestions would be greatly appreciated.

Thanks