You should post this in the overclocking section where you'll get better help.
To overclock manually is much better than using "commander mode" or w/e the motherboard tries to do on its own. How it works is that the 3ghz is actually the FSB multiplied by the multiplier, so its 200 X 15 = 3000mhz. So, to make the cpu faster, you need to increase either the FSB or the multiplier. The multiplier is usually locked, so your option is usually to increase the FSB. When you increase the FSB, your cpu AND your memory increase at the same time. First, you should find the limit of your cpu, then the limit of the memory. Turn the memory down to 100mhz so that it doesn't interfere with the cpu (so if your mobo doesn't post, you know for sure its the cpu). Increase the fsb in small increments and restart; if your mobo beeps, then you've overclocked your cpu successfully. Once your cpu refuses to post, then you've reached the limit of your cpu. You can then increase the voltage to your cpu and try increasing the fsb further; check out the safe limit for your cpu voltage. continue increasing the fsb till you reach the cpu limit. Now that you know how far your cpu goes, its time to see how far the memory goes. Turn the memory back to 200mhz, and the fsb back to 200mhz, and begin increasing again to see the limit of your memory speed. If once you find the limit of your memory, you can set up a memory divider so that your cpu can go as high as it can. You do this by setting the memory to 133 or 166 depending how high you got your FSB to.
btw, if your motherboard doesn't post, you press the little red button next to the SATA ports on the motherboard to reset the bios, then you can do the settings again. Keep an eye on your cpu temperatures and make sure they don't stray too far from normal..
As for your GPU, you can download special software (or it may come with your memory card..) that very simply increases gpu clock and memory speed, this is much easier than cpu.
You then do some stress tests to make sure your OC is stable. If it isn't stable, then turn it down just a bit and try again.
Again, there are some real pros in the OC section so they'll probably help you out better.