It is better if you overclock manually because there might be some settings the "Auto OC Genie" doesn't do.

Am running this rather old system and am playing Battlefield on it (not bad lah, boleh main at 800x600)

CPU : Intel Dual-Core E2140 1.6GHz
PSU : Vantec ION2+ 600W
Mobo : ASUS P5QL-Pro
GPU : Zotac 9600GT AMP! Edition

Days before this I overclocked my PC to 2.4GHz, it was stable and about few minutes ago, I pushed it further to 2.7GHz with only stock cooler (waiting for Venomous X) and am getting 70-ish degree Celcius running full load with Prime95.

Idle : 39`c
Load : ~70`c

Re-run the Prime95 test on full load again, temp goes up to 60ish only. Which is 10 degree lesser than earlier.

This overclocking is fine, right Sifus?