You can multiplier overclock that CPU by 4 bins (400 MHz), but only with a Z75 or Z77 motherboard. There's also BCLK overclocking, but that's not going to get you very far and overclocks other parts of the system that really don't respond well to overclocking.
Overclocking the i5 is possible on only selected few H77/H75 motherboards without increasing the Bclk (Base Clocks).. These motherboards increase the turbo frequency and force the processor to run at the turbo frequency all the time... quite neatly done
Intel not good y u lock down the multiplier?