The Pentium® Pro processor family is Intel's next generation of performance for high-end desktops, workstations and servers. The family consists of processors at 150 MHz and higher and is easily scalable to up to four microprocessors in a multiprocessor system. The Pentium Pro processor delivers more performance than previous generation processors through an innovation called Dynamic Execution. This is the next step beyond the superscalar architecture implemented in the Pentium processor. This makes possible the advanced 3D visualization and interactive capabilities required by today's high-end commercial and technical applications and tomorrow's emerging applications. The Pentium Pro processor also includes advanced data integrity, reliability, and serviceability features for mission critical applications.

The Pentium Pro processor is the next in the Intel386™, Intel486™, and Pentium family of processors. The Pentium Pro processor implements a Dynamic Execution microarchitecture—a unique combination of multiple branch prediction, data flow analysis, and speculative execution.
The Pentium Pro processor is upgradable by a future OverDrive® processor and matching voltage regulator module described in Section 8.
Increasing clock frequencies and silicon density can complicate system designs. The Pentium Pro processor integrates several system components which alleviate some of the previous system burdens. The second level cache, cache controller, and the Advanced Programmable Interrupt Controller (APIC) are some of the components that existed in previous Intel processor family systems which are integrated into this single component. This integration results in the Pentium Pro processor bus more closely resembling a symmetric multiprocessing (SMP) system bus rather than resembling a previous generation processor-tocache bus. This added level of integration and improved performance, results in higher power consumption and a new bus technology. This means it is more important than ever to ensure adherence to this specification.
A significant new feature of the Pentium Pro processor, from a system perspective, is the built-in direct multiprocessing support. In order to achieve multi-processing for up to four processors, and maintain the memory and Input/Output (I/O) bandwidth to support them, new system designs are needed. In creating a system with multiple processors, it is important to consider the additional power burdens and signal integrity issues of supporting up to 8 loads on a high-speed bus.
from the Intel site.