Is it an 800EB or a 600E?

Intel makes two version's of the 800EB. One for OEM and one for retail. Here are the Stepping and CPUID info taken from Intel's S-spec information sheet.

Pentium III 800EB

Now let's take a look at the S-spec of the Retail and OEM P3-600E:

Pentium III 600E

Notice that the Stepping and CPUID numbers are the same. In other words, a program like WCPUID can not tell you if you have a 600E or an 800EB because they would produce the same results. 

Most people think that Intel has different manufacturing lines for different speed chips when the truth is all the chips come off the same line. Generally, the chips at the center of the silicon wafer can run faster than those on the edge. The chips are tested for their maximum speed then placed in the corresponding speed line up. If the chip runs at 800Mhz, it's sold as a 800Mhz. If it runs at 1,000Mhz, it's sold as a 1000Mhz chip and so on. This is also true of AMD and other chip makers.

In chip manufacturing, you will encounter a term known as the Yield Curve. The Yield Curve is expressed as a percentage. When Intel say their yield is 80%, it means that 80% of the chips coming off the line can run at their current maximum speed. As the manufacturing process improves over time, the Yield Curve gets higher and higher until nearly all the chips coming off the line can run at maximum speed. 

The problem for Intel is when all their chips can run at maximum speed, because of high yields, they can't really sell them at their true speed because of demand. Most people don't buy the fastest chip made because of price. People still want to buy the less expensive 550 and 600Mhz chips. So what does Intel do when nearly all their CPUs can run at maximum speed? You guessed it. They just package their high speed chips as low speed chips and sells them at the lower price. In the case of the 600E and 800EB it was easy because nothing needed to be change since the multiplier is the same. The only difference between a 600E and an 800EB is the label. One say 600Mhz and one say 800Mhz. Everything else is the same. If I were to remove the label from those two CPUs; there is no test you can perform to determine which one is which.

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