Sharky Extreme has posted a review on the Celeron 600Mhz. Here a snipped:

When Intel first announced the Celeron processor, I´m not sure they were ready for the impact it would have on the desktop market. Initially designed to offer value consumers an alternative to the higher priced Pentium II processors, the original Celeron 266, and subsequent Celeron 300, were essentially cache-less Pentium II processors using the Deschutes core. Intel announced the Celeron 266 at the same time as the Pentium II 350 and 400 CPUs, which left the previous Klamath core behind. The cache-less Celeron 266 was met with derision from the business community, and standard Winbench and Winstone scores were very low in comparison to Pentium II processors. Sadly, the Celeron 266 and 300 were thus relegated to the extreme low end of the business PC scale.

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