Intel Pentium III 650 Mobile MMC-2 Module
Slowest had been Pentium II or even Celerons, usually top one you could upgrade is Pentium III 850Mhz, still expensive as hell as it is rarity.
Looks like such with heatsinks:
Idea is to put chipset and CPU, plus VRM on one module.
Such way if you have slower cheaper CPU you can have simpler VRM, and for top chips it will be best.
Link to list - http://www.cpu-world.com/Related_CPUs/MMC-2_P6.html
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