Upgrading My Computer

[Cristoforo]

Im looking to spend only about $400 dollars so I may only be able to upgrade 1 thing. So i'm looking for some help to prioritize what I should get first, and then once I get some more $$, what I should get next.
I currently run with all the settings at max except the shadows, and I get 20 FPS in Dalaran and 40 in other Capital cities. The problem is that with ICC 25 my FPS drops to around 10 - 20.

Computer Specs:
AMD Athlon(tm) 64 X2 Dual Core Processor 5200+
2.71 GHz, and 2.00 GB of RAM
GeForce 7600 GS

I know my computer specs may not be great (or may be horrible I don't really know), but I need a little help.

[chaud]

Save another $400 and build a new computer.