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SpeedStep
Intel® SpeedStep™ Overview
Most important, the new processors, rated at frequencies of 600MHz and 650MHz, will be the first to
incorporate an innovative performance technology called Intel® SpeedStep™ technology. Built into certain
mobile Pentium III processors, this technology from Intel provides near-desktop performance with all the
benefits of mobility. When connected to an AC power source, mobile Pentium III processors featuring Intel
SpeedStep technology will deliver near-desktop-level performance. When working on battery, the mobile
PC automatically detects the change and drops both the processor clock frequency and voltage to deliver
outstanding performance without compromising battery life. This new technology will be available in the
thinnest and lightest mobile PCs, so users won’t have to compromise in order to enjoy the mobility they have
come to expect.
How it Works
Mobile Pentium III processors featuring Intel SpeedStep technology can be switched between two perfor-
mance modes—maximum performance and battery-optimized performance—either automatically or by
user command. By default, mobile PCs with mobile Pentium III processors featuring Intel SpeedStep tech-
nology detect when they are plugged into or unplugged from an AC outlet. When a system is unplugged, the
processor core automatically drops to a lower frequency. At the same time, the operating voltage of the
processor drops to a lower voltage. Plug that system back into an outlet, and the processor automatically
speeds back up to peak frequency and voltage.
Users can also manually adjust the Intel SpeedStep technology mode. For example, if a user needs to con-
duct a presentation away from an outlet, he or she can use the Intel SpeedStep technology applet to put the
mobile PC into maximum performance mode. The applet is accessed via an icon in the Windows* Taskbar.
When the presentation is complete, the system can be put back into battery-optimized performance mode.
When switching performance modes, Intel SpeedStep technology can reduce the active power of the proces-
sor up to 45% while maintaining up to 80% of the maximum performance. Switching voltage levels provides
significant power savings, because power consumption occurs in proportion to the square of voltage. By
contrast, clock frequency has a linear relationship with power consumption. The result: A slight reduction in
voltage yields a significant impact on power savings. Of course, the overall impact on battery life depends on
the application running and the design and components of the mobile PC.