How Sandy Bridge Works

By: Jonathan Strickland

Clock Cycles and Controversy

The launch of Sandy Bridge wasn't flawless. One decision Intel made that upset some computer enthusiasts was the decision to move the clock generator for the processor off the motherboard and onto the chipset itself. To understand why that would upset anyone, we need a quick reminder about clock cycles.

A clock cycle on a processor is an electronic pulse in which a processor can complete a basic operation such as retrieving a specific data point. Most computational operations actually require multiple clock cycles. Faster processors can complete more clock cycles per second than slower processors. We measure this in hertz -- the number of cycles per second. A 1-gigahertz processor can complete a billion cycles every second.


Manufacturers build in limits or caps in microprocessors. Many microprocessors are capable of completing many more cycles per second than the manufacturer allows. There are a couple of reasons to limit the clock speed on a microprocessor. First, microprocessors generate heat, and making them run as fast as they are able to will ramp up the heat production significantly. Without sufficient cooling measures in place, these microprocessors can fail as things heat up. Second, by imposing limits on a single microprocessor, the company can market the same chip with a less restrictive clock speed cap at a new price to people willing to pay for the speed.

One way to get around this restriction is to overclock your processor. Overclocking depends upon the equipment you own -- there's no single approach to overclock your computer. But essentially you use software -- and sometimes a little tweaking of actual hardware -- to allow your processor to run at a faster clock speed than the manufacturer normally allows.

When Intel moved the clock generator, which controls the clock speed and synchronizes processor functions, it also locked down the clock speed on most of the chipsets for Sandy Bridge. Some chips will allow overclock enthusiasts to give their processors a modest boost in speed. But it appears that if you want to really be a speed demon, you'll have to purchase one of the more expensive Sandy Bridge chipsets that doesn't include the clock-speed lock.

That wasn't the only controversy to plague Sandy Bridge. Next, we'll look at some errors that resulted in microprocessor underperformance.