Intel Pentium Identification

1.1 CPU Part Number - Prefix

The standard P5 Pentium (P5, P54C, P54CS, P54CQS, P55C) processors have four different part number prefixes. Processors with the "A-" prefix are the most common one (excluding Pentium MMX). There are processors from 60 MHz to 200 MHz. "A" prefix processors were built in PC systems.

Older processors that came in a box were labled with "PCPU-". These are the most rare CPU prefixed, because at that time, most processors were sold in PC systems. Later boxed Pentiums had the "BP" prefix. These are rarer than "A" but not as rare as "PCPU" by far.

"FV-" (PPGA) packages are most common for the Pentium MMX and faster clocked Pentiums.

1.2 CPU Part Number - Processor Model

The original P5 on socket 4 have the processor model 80501. P54C, P54CS and P54CQS for socket 5 are called 80502. Pentium MMX processors have 80503 as their processor model number.

1.3 CPU Part Number - Frequency

P5 has two members: A 60 MHz and a 66 MHz clocked version. The P54C/CQS/CS have the following frequencies: 75, 90, 100, 120, 133, 150, 166 and 200 MHz. MMX integrated Pentiums (P55C) ranged from 166 to 233 MHz.

• P5: 50 MHz (ES), 60 MHz, 66 MHz
  
• P54C/CQS/CS: 75 MHz, 90 MHz, 100 MHz, 120 MHz, 133 MHz, 150 MHz, 166 MHz, 200 MHz
  
• P55C: 166 MHz, 200 MHz, 233 MHz
  

What is an SSpec?

We can use the so called sSpec to exactly identify Intels IC parts. sSpecs are composed of 5 characters (rarely: 4 or 6), from letters and numbers.

Production parts have sSpecs beginning with an "S", like "SX835, SZ994, SU099, SL23L and SR050. Rare engineering sample parts have QSpec numbers, such as Q0352, Q0666 or Q0128 or even come completely without any specification number. "PCPU-" parts also don't have SSpecs.

What is the iCOMP Index?

The Intel Comparative Microprocessor Performance Index (iCOMP) is a benchmark created by Intel that allowed the customers to compare the performance of Intel's various processor models & families. The iCOMP was introduced in 1991, starting from a Intel i486 25 MHz as iCOMP Index=100.

iCOMP Versions

iCOMP 1.0:

• Introduced 1991
• Compares from 386 SX-16 processors to the P54C Pentium
• 16 & 32 bit benchmarks
• i486 SX-25 as iCOMP Index = 100

iCOMP 2.0:

• Introduced 1997
• came with the Intel Pentium MMX
• only 32 bit benchmarks
• higher focus on FPU performance, because competitors (AMD, Cyrix) FPU performance were inferior to Intel's
• Intel Pentium 120 as iCOMP 2.0 Index = 100, because the Pentium 120 scored 1000 in iCOMP 1.0

iCOMP 3.0:

• Introduced 1999
• mainly focuses on SSE performance
• Intel Pentium II 350 MHz as iCOMP 3.0 Index = 1000

As soon as Intel introduced the Pentium 4, Intel switched to frequency for performance classification.

Oh, sounds way too complicated? No problem, I have written a small tool that decodes the FPO number! Go to the DOWNLOADS section now!

The FPO (finished process order) number gives you exact information on the CPU production date. You can find these codes on almost every CPU by Intel. Earlier parts have an 8 digit FPO number. With P54C, Intel introduced a serialization code.

4.1 Plant Code

Where the processor was manufactured.

4.2 Production Year

The year the processor was manufactured in. E.g. for Intel Pentium: "5" means 1995, "7" means 1997.

4.3 Production Week

The week the processor was manufactured in.

4.4 Lot Number

Sorry, but there is no information available at this time.

4.5 Serialization Code

Sorry, but there is no information available at this time.

The year that Intel asserted copyright to the CPU architectural design. The first code should show the year of the original outline, the second may display the year with the latest revision made on the chip.

Pentium 60 has a core voltage of 5 Volt

Pentium 66 has a core voltage of 5.15 Volt (-> also SSpec dependent)

Ceramic Pentiums (P75 to P200), CPGA package

... have a core voltage depending on two types of voltage.

The markings are the following:

• SSS - Standard Voltage Range: 3.135V to 3.6V, 3.3V recommended
• VSS - VRE Voltage Range: 3.4V to 3.6V, 3.3V recommended

The core voltage of Pentium MMX processors are directly written to the pin-side of the CPU.

Sources

• VRE voltage: http://rpmfind.net/linux/netwinder.org/misc/docs/i386/24268703.pdf
• Country code: http://www.cpu-world.com/forum/viewtopic.php?t=3742
• Copyright marking: http://www.antiquetech.com/identification/intel_chip_markings.htm
• P5 voltage: http://en.wikipedia.org/wiki/P5_%28microarchitecture%29
• iCOMP Index: http://de.wikipedia.org/wiki/ICOMP_Index
• SSpec: http://de.wikipedia.org/wiki/SSpec
• Part Number: http://www.cpu-world.com/info/id/Intel-Pentium-identification.html

All information supplied without any liability. Subject to change without prior notice.