I wanted to use a mobile pentium 4 but I'm sure it will work at half the multiplier due to the speedstep. Unfortunately my motherboard doesn't have many overclocking options. Many years ago I remember seeing a large number of modifications that involved fiddling with the 478 processor pins to get interesting stuff, but it all seems to have disappeared from the internet.

I want to use the mobile pentium 4 because it's a barebone MSI Mega PC 651 that generates a significant amount of heat due to the little internal space, and unfortunately it didn't come with the original cooler, and it has a bad adaptation of a cooler socket 939 (I think) which will not provide the best heat dissipation

I chose the SL724 Pentium 4 Mobile 2.66, it has (supposedly) a low tdp of 66w. Although I also have a 2.2ghz SL6Q7 with 58w tdp. My main goal is to have a CPU that runs cool, with the lowest voltage possible, I don't care about the clock, I just want to make sure I have the best I can.