Hardware Knowledgebase - What is the Mhz Speed of PC2700, PC3200, PC3500, PC4000, or other types of DDR DRAM? - HardwareFAQs: powered by neofaq: "FAQ
What is the Mhz Speed of PC2700, PC3200, PC3500, PC4000, or other types of DDR DRAM?
ANSWER

The numeral portion of DDR memory represents the 'MB/s' of the RAM, so PC2700 is rated at 2.7GB/s (2700MB/s) and so forth. However, when configuring your RAM the names of the memory are actually related to their speeds as follows:

PC2100: 266Mhz
PC2700: 333Mhz
PC3200: 400Mhz
PC3500: 433Mhz
PC3700: 466Mhz
PC4000: 500Mhz
PC4200: 533Mhz

Note that many of these RAMs are NOT officially recognized by standards committees because technically anything above DDR400 speeds are not officially supported by chipsets.

Most of the really high speed RAM such as 433Mhz and above (PC3500 and above) go beyond standard specs and are useful for FSB overclocking above 200Mhz.

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