I have one of those P4-Ms you speak of and it'll work in any motherboard that will support a Northwood A. However, a standard 845/855/865/875 chipset doesn't know that the chip has two multiplier settings and will always run the chip at the lowest one, which is 12x, or 1.20 GHz for all Pentium 4-Ms. You'd need a mobile chipset like my laptop's 845MP to access the higher multiplier and use SpeedStep.
OP: The 3.06 chip is NOT a Pentium 4-M and is in fact the desktop Northwood B. (P4-Ms are all 400 FSB and only went up to 2.60 GHz.) It should work if the desktop's motherboard supports Northwood Bs, Cs, or 478 Prescotts. It may not work if the motherboard doesn't support a 533 FSB, not for any physical reason (the chip would just run at 2.30 GHz) but that the BIOS doesn't recognize the CPU and may not boot. But even if the chipset is a 400 FSB only, if you have the CPU, try it. You won't hurt it. The only way that you could hurt that chip would be to try it in a socket 478 Willamette board that runs at a 1.75 Vcore and doesn't have the BIOS to recognize the Northwood As that run at 1.55 volts. Putting 1.75 volts to a Northwood is a good way to get SNDS. (Man, it's been a while since anybody has discussed SNDS around here
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