You can overclock your CPU by 400 MHz by increasing the Turbo Boost multipliers. You could also increase the BCLK, but I wouldn't recommend that.
This Intel diagram is actually about the Core i5-2500, but the Core i5-3550 features the same clocks, so it works exactly the same way:
If your motherboard supports "multicore enhancement", you can cheat the system and set the multiplier to 41 regardless of the number of active cores. The GA-Z77M-D3H doesn't seem to support that feature though, as far as I can tell.