There's almost ZERO benefit in most games to overclocking that CPU. Here's some info:
http://www.ocaholic.ch/modules/smartsection/item.php?itemid=1061&page=13
The "HIGH" results are what you want (1920x1080) and when all games are averaged, going to 4.5GHz only increased performance by 1%!!
That's hardly worth a noticeable increase in FAN NOISE, and if you are using VSYNC and capped already at 60FPS it won't make any difference (in the future with a much better video card overclocking WILL matter more). I do recommend getting a better CPU Cooler than stock for noise, but I don't recommend overclocking much. At most, I'd just increase all the CPU CORE multipliers to "41" (and test with a CPU stress application, as well as MEMTEST)...