Intel Pentium III 866

I have two other Pentium III 866's: one cC0-stepping with slot 1 packaging and one cC0-stepping with S370 packaging just like this CPU. The only difference is that this one is equipped with the newer cD0 revision core. At that time Intel also changed the printing on the chips a bit: the big Intel logo disappeared and the black rectangles with chip information became smaller.

In performance terms this CPU is identical to the cC0-stepping. As far as I know most changes have been made in thermal dissipation and optimizations to reach higher clock frequencies.