Architecturally it’s the biggest change we’ve seen since Conroe, although looking at a high level block diagram you wouldn’t be able to tell. Unlike Lynnfield, Sandy Bridge isn’t just about turbo (although Sandy Bridge’s turbo modes are quite awesome).

For those of you who want more, 4.6-4.8GHz is within reason. All on air, without any exotic cooling. Relying on single-click motherboard auto-overclocking alone, the 2600K is easily at 4.4GHz. The only thing keeping us from 4GHz is a lack of competition to be honest. Even with two cores active, the 32nm chip can run them both up to 3.7GHz. When running a single threaded application, the Core i7-2600K will power gate three of its four cores and turbo the fourth core as high as 3.8GHz. Today, Intel quietly finishes what it started nearly a decade ago. With each subsequent generation Intel inched those clock speeds higher, but preferred to gain performance through efficiency rather than frequency. Within a year the clock (no pun intended) was reset and we were all running Core 2 Duos at under 3GHz. Despite being on a dedicated quest for gigahertz the company stopped short and the best we ever got was 3.8GHz. Intel never quite reached 4GHz with the Pentium 4.

I5 vs core 2 duo