The 265 flavours of Intel's Pentium 4
 

The fact is that there's been a staggering 265 versions of the Pentium 4 in its different packagings. That's due to a combination of sockets, cache, clock speeds, the process used and the steppings of the chip's core. Then there's boxed Pentium 4s with fans, with heatsinks, without fans, and the like

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