If you already have 1 stick of 512 memory, just get another single stick of 512, not the 2x256 you linked to.
The video card you linked to is PCI-e, just a hunch, but since you are currently running a 9600, I am guessing you do not have PCI-e on your mobo, you most likely have AGP. If that is the case, you will need an AGP gfx card, and I would suggest the 6800GT over to 800xl.
The hd is fine.
BE HEARD - Techonvent
DS3 | E6400 - 3.2GHz 24/7 | 2GB OCZ PLat. PC6400 | 6800GT | Zippy 460W
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