Hmm.. Im not sure about the rigs of other people here but "if" you're on a tight budget this setup would be enough to play BF2:
Athlon64 3000+ or 3200+ or 3500+
Nvidia Geforce 6600GT <-- It's old but still would run BF2 fine.
1 GB - 2 GB Ram (Preferably 2gb and Dual Channel on an A64 cpu)
40 gb Hard disk
If you have like a still decent P4 Processor and you dont wanna upgrade everything you can buy yourself a good Videocard and you could even run Oblivion on it. My backup rig is a 1.7ghz P4 but with 1gb ram and a 6800GT and it runs Oblivion and BFV, BF2 with almost everything on high.





costed $350...