I7 3770 is still fine choice for CPU.
I'm not sure can you do this with you board but with z77 and z68 you can push slight OC on non K cpu's of total +400 Mhz for each turbo step.
That should give you some extra performance if you want.
So you should be getting something like this
43 Multiplier for 1 & 2 Cores =4.3 ghz
42 Multiplier for 3 Cores =4.2 ghz
and 41 Multiplier for 4 Cores =4.1 ghz
It is quite easy to do it if your motherboard supports it.
I7 3770 is still fine choice for CPU.
I'm not sure can you do this with you board but with z77 and z68 you can push slight OC on non K cpu's of total +400 Mhz for each turbo step.
That should give you some extra performance if you want.
So you should be getting something like this
43 Multiplier for 1 & 2 Cores =4.3 ghz
42 Multiplier for 3 Cores =4.2 ghz
and 41 Multiplier for 4 Cores =4.1 ghz
It is quite easy to do it if your motherboard supports it.