Leem123 :
I have a Coolermaster plus cooler! Would that put my temps up? Also how do i change the multiplier?
Yes your temps will be increased when you overclock. I would recommend you read a few sources before attempting to overclock, there are some things to keep in mind about it.
This is a very comprehensive guide on it, I'd be glad to answer any specific questions you have, but this makes it easier since it has everything laid out and better articulated (meaning I'm lazy)
http://www.overclock.net/t/525113/phenom-ii-overclocking-guide
Really though, you already have a decent cooler. My advice would be to keep it simple.
1. Download Hw monitor so you can watch your temps
2. Download Prime 95 so you can test your stability
3. Increase your multiplier one half step at a time, run stability tests each time until you hit 3.8-4.0GHZ and stop there.
Increasing multiplier is the simplest way to overclock, as far as how to go about it, you can use AMD Overdrive. Its a free download with a built in stability test (so you don't need Prime 95) although I've found its temp readings aren't always accurate, so I suggest HW monitor. As long as the CPU doesnt go over 62c, you're fine, thats the max safe temp of the Phenom IIs. Although honestly it probably would be fine if it hit 70c as long as its not long-term sustained.
Always keep in mind that overclocking voids your warranty on the CPU. So there is a risk, but theres a risk in anything thats worth doing.