SpeedStep

Enhanced Intel SpeedStep Technology is sometimes abbreviated as EIST. Intel's trademark of "Intel SpeedStep" was cancelled due to the trademark being invalidated in 2012.

Microsoft has reported that there may be problems previewing video files when SpeedStep (or the AMD equivalent PowerNow!) is enabled under Windows 2000 or Windows XP.

Solaris has supported SpeedStep since OpenSolaris SXDE 9/07. Older versions of Microsoft Windows, Windows 2000 and earlier, need a special driver and dashboard application to access the SpeedStep feature. Intel's website specifically states that such drivers must come from the computer manufacturer; there are no generic drivers supplied by Intel which will enable SpeedStep for older Windows versions if one cannot obtain a manufacturer's driver. Under Microsoft Windows XP, SpeedStep support is built into the power management console under the control panel. In Windows XP a user can regulate processor speed indirectly by changing power schemes. The "Home/Office Desk" setting disables SpeedStep on AC power, the "Portable/Laptop" power scheme enables SpeedStep, and the "Max Battery" uses SpeedStep to slow the processor to minimal power levels as the battery weakens. The SpeedStep settings for power schemes, either built in or custom, cannot be modified from the control panel's GUI, but can be modified using the powercfg. exe command line utility. The Linux kernel has a subsystem called "cpufreq", tunable by power scheme and command line, devoted to the control of the operating frequency and voltage of a CPU. Linux runs on Intel, AMD, and other makes of CPU. Newer version Windows 10 and Linux kernel support Intel Speed Shift Technology. In contrast, AMD has supplied and supported drivers for its competing PowerNow! technology that work on Windows 2000, ME, 98, and NT.