Um, I dont know if you need to upgrade. It. What kind of games are we talking here? You said your not a dedicated gamer, so are we talking things like solitaire and older games, like AOE? If so, your system specs are just fine. If your wanting to get into more intense game, then make sure it uses the latest pixel shader and vertex shaders as more and more games (thief III for example) are requiring that. FX series, ATI, etc. Anyhow, its all upto what kind of games and what kind of work you're doing on it. Otherwise, you should be fine.
If you argue with an idiot he will drag you down to his level and beat you with experience.
I am not a fast writer.
I am not a slow writer.
I am a half-fast writer.