"The P4 2.4B runs with a 533 MHz FSB (hence the 2.4B ) which gives the processor up to 4.2 GB/s worth of bandwidth."
"To avoid confusion among consumers, Intel has added an "A" to show that it is a Pentium 4 based on Northwood core and 400Mhz FSB and a "B" to differentiate between a 400Mhz FSB and a 533Mhz FSB Pentium 4 "Northwood"."
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