Well, I've got bad news and good news:
Bad news (as stated by derFunkenstein
): Intel Sandy Bridge processors are overclocked by increasing the CPU multiplier. Because of this, there are processors with a "K" suffix that indicate an unlocked multiplier (aka, they can be overclocked). You have to get into the i5 family before you get processors like the i5-2500K
that are overclockable. Moral of the story, you're not going to get any kind of significant overclock from your i3-2100.
Good news: Intel Sandy Bridge processors run circles around the competition. Even your i3 can outgame AMDs Phenom and FX procesors.
Here's another example.
Enjoy your i3, it's a very solid performer.
Main: i5-3570K, ASRock Z77 Pro4-M, Asus GTX660 TOP, 500GB Crucial BX100, 2 TB Samsung EcoGreen F4, 16GB 1600MHz G.Skill @1.25V, Silverstone PS07B
HTPC: A8-5600K, MSI FM2-A75IA-E53, 4TB Seagate SSHD, 8GB 1866MHz G.Skill, Hand-Built Wood Case