Overclocking a computer means operating it at a higher clock rate than that specified by its manufacturer; for example, a 2 GHz chip might be clocked at 2.1 GHz to squeeze more performance out of it. Does overclocking disprove the famous aphorism, "There's no such thing as a free lunch", or is there a hidden cost? If so, what is the cost of overclocking?

Question

What will be an ideal response?

Answer 1

Chip manufacturers make processors that are capable of operating at a certain clock rate. That rate is determined by the manufacturing process, the geometry of the elements that make up the transistors and connections, the electrical properties of the semiconducting materials, and the circuit itself. For any given complex chip, the devices coming off the production line will have a spread of characteristics. The operating speed of the device you buy is guaranteed by the manufacturer. Of course, the particular device you buy might be at the high?end of the speed band; that is, it may be capable of operating at a greater clock rate than its nominal clock frequency.

Because of the margin between the published operating speed of a processor and the actual maximum operating speed of the actual sample you buy, your processor will probably work at a higher frequency.

Overclocking means running a device at a higher frequency than its specification. Today, you can run processors faster and even change the processor’s operating voltage. It’s even possible to change how the DRAM operates. You can, if all goes well, end up with a system that costs a lot less than a system with a higher specification and higher price.

However, overclocking is not guaranteed. Overclocking reduces margins (for example, voltage and temperature margins). You might overclock your processor and then find it stops operating on a very hot day. For many computer enthusiasts, overclocking is indeed the free lunch that’s paid for by the cautious device characterization by the manufacturers (i.e., by selling a chip marked as 2.5 GHz when it will operate at 2.7 GHz. On the other hand, the increase in temperature at the new frequency may be harmful and shorten the life of the chip. Equally, the chip may fail when certain sequences of instructions are executed. If you were a professional and overclocked a chip in a commercial application that later failed, you could reasonably expect a lawyer to come knocking at your door.