Intel 64 bit
 

Nearly 18 months after rival AMD released its 64-bit processors, Intel quietly added its first 64-bit Pentium 4 microprocessors to the market on Sunday. Four versions of the Intel Pentium 4 6XX series were announced at speeds up to 3.6-GHz, a frequency grade lower than the existing 5XX series. Prices will range from $224 to $605.

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