I know that this thread isn't supposed to be about voltages and temperatures, but I'd like to point something out to the people pushing from a nice 70-75C at 4.7 GHz to try to hit 4.9GHz at 90-95C.
You're going to hit a thermal wall and your CPU is going to throttle itself due to being near or at TJMax at some point. There are programs out there that run significantly hotter than Prime95 (Such as Intel Burn Test or even some folding WUs) and your'e going to smoke your chip or at least throttle yourself into low performance until the temperatures cool down unless you change it.
Also, you're going to be consuming huge amounts of power and even if you've changed your board to use current/power monitoring instead of thermal monitoring, you're going to get hidden internal throttling due to power consumption. I know, because I tested this. I actually found that at 4.7 GHz my GFlops in IBT could be anywhere from 123.2 up to 127.1 depending on my Vcore. The lower the Vcore, the higher the GFlops and thus the better my performance was.
My point here is that it's not all about how fast your clock is; it's about how efficient your overclock is. Temperature and power are closely related, as temperature is simply electrical power that has been wasted, converted into heat instead of into processor cycles. So for those of you struggling to hit 4.8 or 4.9 GHz at 1.45 to 1.48 Vcore and 90+ C, you're shooting yourselves in the foot. Either sell your CPU and buy a new one, hoping that you get a "golden" chip, or just clock yourself down to 4.6 GHz and enjoy faster computational performance at a cooler and more power efficient clock.