TECHNOLOGY SPECIAL REPORT
The Insider's Guide to Overclocking

Computer hobbyists for years have tweaked their computers' innards to squeeze out extra bits of performance. Known as overclocking, the practice has long been a holy grail to users who demand maximum performance from their systems.

Overclocking does pose hazards to computer hardware, which is largely the reason that business users have not traditionally adopted the practice. While some small businesses today have turned to overclocking as an alternative to upgrading, the practice is almost never engaged in at the corporate level, James Turley, principal analyst at Silicon Insider, told TechNewsWorld.

Large companies avoid overclocking because it threatens the reliability of their computer systems. "You don't want to put your business at risk by introducing potential failure," Howard Locker, chief architect for IBM's (NYSE: IBM) Desktop and Mobile Development division, told TechNewsWorld.

"IT folks [in large corporations] have no motivation to do it," said Turley. "IT staffs get pretty conservative; they are no longer techno cowboys."

While the practice is almost never seen in large corporations, the overclocking underground seems to be gaining a great deal of momentum, with user groups popping up all around the Net to offer tips and tricks to would-be overclockers. Moreover, manufacturers have begun to sell not only overclocking kits, but also preconfigured overclocked systems.

Anatomy of an Overclocked System

Computers are designed to operate at a speed regulated by the system clock. All of the other components fall into step to operate at the determined clock speed. Think of a metronome sitting atop a piano. If the musician plays the notes at the tempo regulated by the metronome, all is well with the music. That's what the system clock does for a computer.

The computer clock sets the pace for the system bus -- or bridge -- that connects all of the components to the processor. The bus tells the processor at which speed to perform all instructions.

Because the voltage setting on the main board controls the bus speed, if you change a jumper setting on the main board, you can increase the voltage and speed up the system clock. Of course, if you change the jumper settings improperly, the clock could dramatically slow down the system.

A faster clock speed means higher operating temperatures in all the components installed on the motherboard, especially the CPU. If you exceed the temperature ratings for a processor or a motherboard, problems can crop up.

Typically, skilled overclockers can throttle the speed of the microprocessor to gain as much as a 30 percent performance boost. However, all but the most skilled overclockers will achieve only a 5 percent increase.

"That's a lot of effort for a minimal return and a great risk to the system," said Locker. But for users obsessed with performance, even a 5 percent hike in system power can cause notable improvement in performance over time.

What's the Risk?

A short foray onto the Internet will provide instructions and parts lists to overclock just about any system. An investment of less than US$50 can give you all you need to do the job. But be careful, experts say: A little bit of knowledge can give you all the tools you need to destroy your system. Intel (Nasdaq: INTC) warns that overclocking any Intel processor will void your warranty.

"Every component is designed and tested to operate at a particular frequency," said Locker. When one or two parts get out of range, he said, it can ruin the hard drive, destroy data or lock up the system. Overclocked systems can suddenly display intermittent problems, and they can develop compatibility issues with various peripherals.

Overclocking techniques cannot address all of the essential components in a system. One component in particular, the core logic, always stays at the same speed, which can cause miscommunication with the processor. If nothing else happens, overclocking will almost always shorten the processor's life.

Ultimately, an overclocked system can burn itself out. However, some expert overclockers say that if the process is done properly, the CPU will become obsolete long before it fails.

Manufacturer Overclocking

The chip-making process itself creates the climate for users to soup up their systems through overclocking. But most computer makers avoid selling overclocked systems -- at least overtly.

Although processors are assembled in clean rooms that exceed the sterile conditions in a typical hospital operating room, anomalies occur in the silicon of a small percentage of computer chips. The anomalies in a processor batch define that batch's speed range -- the range of speeds at which the processor can safely operate.

"Any given chip has four or five chip speeds," Turley explained. "They are otherwise the same identical chip."

Manufacturers can either throw out the slower chips, sell all the chips at the slower speed, or sell different speeds at different prices, he said. This process, known as "speed sorting" or "spinning," lets economics take over for physics. "Chip makers artificially set the chip speed lower to get volume sales at the sweet spot of the market," Turley said.

Another reason why overclocking works, he added, is that all chips have a headroom of 5 to 25 percent.

Beating the Clock

Not all manufacturers look on overclocking as a dangerous activity. Unscrupulous computer makers might hide the fact that a system is overclocked. Others, however, use overclocking as a marketing point. For example, Systemax sells computer systems with built-in overclocking features to gamers. And chip manufacturer AMD (NYSE: AMD) partners with computer makers that include dual BIOS features to assist overclockers.

"I think there is hidden horsepower [in processors] that can be unlocked simply," said Toby Wilson, director of engineering at Systemax. Wilson said his company bundles software that interfaces with Windows to change the motherboard settings. The software restricts overclocking to safe limits.

"There is no one defined level of what overclocking is," he said. "There is definitely a range of performance available when we design our systems." According to Wilson, hobbyists typically like to overclock their machines themselves. "Many users want the ability to set variable speeds."

However, Wilson added that if the manufacturer designs a system for overclocking, the system won't be harmed, and a reputable manufacturer will stand behind the speed increase with a warranty. "Part of the engineering phase is to identify the requirements for each system," he said. "We define, preload and set the hardware; the PC is safely overclocked."