Abbreviated as EIST, an
Intel thermal and power management technology that allows the the
processor performance and power consumption levels to be modified while a system is running. Enhanced Intel SpeedStep Technology works via
application software, which changes the bus-to-core frequency ratio and the processor core voltage. The operating state is determined by things such as the system power source, the processor thermal state, and even the
operating system policy. Enhanced Intel SpeedStep Technology is supported on current and future generations of Intel Pentium M Processors.