Hardware Reference
In-Depth Information
FIGURE 1.5
An active heat sink
Photo credit: http://en.wikipedia.org/wiki/GNU_Free_Documentation_License Fir0002/Flagstaffotos
Active cooling systems require power to operate, increasing the amount of power
required by the PC. Some computers have energy-effi cient cooling fans that can be adjusted
in the BIOS setup to operate only if the processor's temperature (as evaluated by an internal
thermometer) is over a certain value.
BIOS stands for Basic Input/Output System. It's software on a chip on
the motherboard that controls the boot process and low-level hardware
access. It has its own setup program, which you can access by pressing a
specific key as the computer is booting. Watch onscreen as the computer
boots for information about which key to press. Because it's stored on a
read-only memory (ROM) chip, it's sometimes referred to as the ROM-
BIOS. You'll learn about ROM later in this chapter.
Water can also be used as a coolant, instead of air from a fan. In a water-cooled system,
a pump circulates water through tubing that runs between the components that generate
heat. The tubing passes through passive heat sinks affi xed to the chips (usually with a heat-
conductive adhesive compound), carrying the heat away from the chips. The chips involved
can include not only the main processor on the motherboard, but also the main processing
chip on the graphics card and perhaps some of the other larger chips on the motherboard
too. Water cooling is effective, and it allows systems that otherwise might run too hot to
