DDR-SDRAM Specs, Continued
DDR-SDRAM comes in CAS-latencies of 2 and 2.5 ns. Obviously the CAS 2 DDR-SDRAM is the faster and thus more expensive of the two. JEDEC once defined that CAS 2/PC266 DDR-SDRAM should be called 'DDR-266A' and the CAS 2.5/PC266 DDR-SDRAM 'DDR-266B'. Here's the part out of the official JEDEC-spec:
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