What is Pentium Pro?

PROCESSOR SPECIFICATIONS

	Manufacturer:	Intel
	Model:	Pentium Pro
	Year:	1995
	Transistors:	5,500,000
	Microns:	0.6µ

If the regular Pentium is an ape, this processor evolved into being human. The Pentium Pro (also called "P6" or "PPro") is a RISC chip with a 486 hardware emulator on it, running at 200 MHz or below. Several techniques are used by this chip to produce more performance than its predecessors. Increased speed is achieved by dividing processing into more stages, and more work is done within each clock cycle. Three instructions can be decoded in each clock cycle, as opposed to only two for the Pentium. In addition, instruction decoding and execution are decoupled, meaning that instructions can still be executed if one pipeline stops (such as when one instruction is waiting for data from memory; the Pentium would stop all processing at this point). Instructions are sometimes executed out of order, that is, not necessarily as written down in the program, but rather when information is available, although they won't be much out of sequence; just enough to make things run smoother. Such improvements to the PPro resulted in a chip optimized for higher end desktop workstations and network servers.
It has two separate 8K L1 cache (one for data and one for instructions), and up to 1 MB of onboard L2 cache in the same package. the onboard L2 cache increased performance in and of itself because the chip did not have to make use of an L2 cache on the motherboard itself. PPro is optimized for 32-bit code, so it will run 16-bit code no faster than a Pentium, which is a big drawback. It's still a great processor for servers, being it can be in multiprocessor systems with 4 processors. Another good thing about the Pentium Pro is that with the use of a Pentium 2 overdrive processor, you have all the perks of a normal Pentium II, but the L2 cache is full speed, and you get the multiprocessor support of the original Pentium Pro.

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