Features

6.2.4Enhanced HALT Snoop or HALT Snoop State, Grant Snoop State

The Enhanced HALT Snoop State is used in conjunction with the new Enhanced HALT state. If Enhanced HALT state is not enabled in the BIOS, the default Snoop State entered will be the HALT Snoop State. Refer to the sections below for details on HALT Snoop State, Grant Snoop State and Enhanced HALT Snoop State.

6.2.4.1HALT Snoop State, Grant Snoop State

The processor will respond to snoop transactions on the FSB while in Stop-Grant state or in HALT Power Down state. During a snoop transaction, the processor enters the HALT:Grant Snoop state. The processor will stay in this state until the snoop on the FSB has been serviced (whether by the processor or another agent on the FSB). After the snoop is serviced, the processor will return to the Stop-Grant state or HALT Power Down state, as appropriate.

6.2.4.2Enhanced HALT Snoop State

The Enhanced HALT Snoop State is the default Snoop State when the Enhanced HALT state is enabled via the BIOS. The processor will remain in the lower bus ratio and VID operating point of the Enhanced HALT state.

While in the Enhanced HALT Snoop State, snoops are handled the same way as in the HALT Snoop State. After the snoop is serviced the processor will return to the Enhanced HALT Power Down state.

6.2.5Enhanced Intel SpeedStep® Technology

Enhanced Intel SpeedStep Technology enables the processor to switch between frequency and voltage points, which may result in platform power savings. To support this technology, the system must support dynamic VID transitions. Switching between voltage/frequency states is software controlled.

Note: Not all processors are capable of supporting Enhanced Intel SpeedStep Technology. More details on which processor frequencies support this feature will be provided in future releases of the Intel® Pentium® Processor Extreme Edition and Intel® Pentium D Processor Specification Update.

Enhanced Intel SpeedStep Technology is a technology that creates processor performance states (P states). P states are power consumption and capability states within the Normal state as shown in Figure 6-1. Enhanced Intel SpeedStep Technology enables real-time dynamic switching between frequency and voltage points. It alters the performance of the processor by changing the bus to core frequency ratio and voltage. This allows the processor to run at different core frequencies and voltages to best serve the performance and power requirements of the processor and system. Note that the front side bus is not altered; only the internal core frequency is changed. To run at reduced power consumption, the voltage is altered in step with the bus ratio.

The following are key features of Enhanced Intel SpeedStep Technology:

Voltage/Frequency selection is software controlled by writing to processor MSRs (Model Specific Registers), thus eliminating chipset dependency.

If the target frequency is higher than the current frequency, VCC is incremented in steps (+12.5 mV) by placing a new value on the VID signals and the processor shifts to the new frequency. Note that the top frequency for the processor can not be exceeded.

If the target frequency is lower than the current frequency, the processor shifts to the new frequency and VCC is then decremented in steps (-12.5 mV) by changing the target VID through the VID signals.

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Intel 830 manual Enhanced Halt Snoop or Halt Snoop State, Grant Snoop State, Enhanced Intel SpeedStep Technology

830 specifications

The Intel 830 chipset, introduced in the early 2000s, marked a significant evolution in Intel's chipset architecture for desktop and mobile computing. Known for its support of the Pentium 4 processors, the 830 chipset was tailored for both performance and stability, making it an appealing choice for OEMs and enthusiasts alike.

One of the standout features of the Intel 830 chipset is its support for DDR SDRAM, providing a much-needed boost in memory bandwidth compared to its predecessors. With dual-channel memory support, the chipset could utilize two memory modules simultaneously, which effectively doubled the data transfer rate and enhanced overall system performance. This made the Intel 830 particularly beneficial for applications requiring high memory throughput, such as multimedia processing and gaming.

Another important characteristic of the Intel 830 was its integrated graphics support, featuring Intel's Extreme Graphics technology. This integration allowed for decent graphics performance without the need for a dedicated GPU, making it suitable for budget systems and everyday computing tasks. However, for power users and gaming enthusiasts, the option to incorporate a discrete graphics card remained available through the provided PCI Express x16 slot.

The Intel 830 chipset also boasted advanced I/O capabilities, including support for USB 2.0, which provided faster data transfer rates compared to USB 1.1, and enhanced IDE interfaces for connecting hard drives and optical devices. With its Hyper-Threading technology support, the chipset allowed for improved multitasking efficiency, enabling a single processor to execute multiple threads simultaneously, a feature that was particularly beneficial in server environments and complex computing tasks.

In terms of connectivity, the Intel 830 supported multiple bus interfaces, including PCI Express and AGP, thereby enabling users to expand their systems with various add-on cards. This flexibility contributed to the chipset's longevity in the marketplace, as it catered to a wide range of user needs from light computing to intensive gaming and content creation.

In summary, the Intel 830 chipset combined enhanced memory capabilities, integrated graphics performance, robust I/O features, and flexible expansion options, making it a versatile choice for various computing environments during its time. It played a key role in shaping the landscape of early 2000s computing, paving the way for future advancements in chipset technology. Its legacy continues to influence modern computing architectures, illustrating the lasting impact of Intel’s innovative design principles.