Should I Upgrade CPU or GPU?

Steel Pheonix

Honorable
Jan 23, 2013
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10,510
I have been looking to upgrade my old computer so I can play the latest games without many problems. I don't mind lowering the graphics settings to play, but with the newest games, I can't play them without my computer dragging down a lot.

I am planning on upgrading both my processor and graphics card eventually, but I only have enough money to do one upgrade right now.
I have an Intel Pentium Dual Core 3.20GHz processor and a Nvidia Geforce 6600 graphics card.

which one should I upgrade first, and what are some inexpensive options for their upgrades?