Just change the FSB from 266 to 334? Its that easy with the Gigabyte P35 DS3R? Whats the thing called that you changed ( also did you have to use the F1 + ctrl secret menu thing? ) Detailed instructions please
Basically, you take the FSB (Front Side Bus) and multiply it by the (dun-dun-dun) multiplier which is 9 at default.
For example, the stock setup is 244 x 9 = 2394MHz or 2.4GHz (yay rounding!).
So, if you want 3.0GHz (3000MHz) you divide it by the multiplier. Your multiplier is 9 so you get 333.33 repeating. I just like to round up so I did 334, it's all the same really.
If my memory serves me correctly, you just do the following:
Boot into BIOS
Go down to M.I.T.
Then set the overclock to Manual.
Change the FSB of 266 to 334.
Push F10 to Exit & Save Changes.
System should reboot and viola, you're overclocked.
Unless you have the LOGO screen disabled, you won't know it. But if you do disable it (under Advanced BIOS) this mobo actually shows you the math for the CPU. So before you even boot into windows you can verify that it's overclocked. It will read at the top of the screen something like Q6600 334x9=3.0GHz
*Also, you should disable C1E and EIST feature in the Advanced BIOS (along with the POST logo if you like, same section). This forces the overclock to be maintained at all times. Those features were released by intel to help conserved power consumption. So if you aren't completely utilizing your PC it could drop the multiplier to 6 rendering your FSB of 334 useless because then you're running 2.0GHz.
Oh, and the Ctrl+F1 thing you speak of is really only needed for tweaking RAM timings. It gives a few other advanced options, but that's the main thing is enables you to do in the BIOS.