Editing Pentium III (section)

==Controversy about privacy issues==
The Pentium III was the first x86 CPU to include a unique, retrievable, identification number, called Processor Serial Number (PSN). A Pentium III's PSN can be read by software<ref>{{cite web | url=https://www.buraks.com/p3uns/ | title=P3 Serial Un-Support Page }}</ref> through the [[CPUID]] instruction if this feature has not been disabled through the [[BIOS]].

On November 29, 1999, the Science and Technology Options Assessment (STOA) Panel of the [[European Parliament]], following their report on electronic surveillance techniques asked parliamentary committee members to consider legal measures that would "prevent these chips from being installed in the computers of European citizens."<ref>{{Cite news |date=November 29, 1999 |url=http://www.cnn.com/TECH/computing/9911/29/eu.p3.ban.idg/index.html |title=Advisory group asks EU to consider Pentium III ban |work=[[CNN]]}}</ref>

Intel eventually removed the PSN feature from Tualatin-based Pentium IIIs, and the feature was absent in Pentium 4 and Pentium M.

A largely equivalent feature, the Protected Processor Identification Number (PPIN) was later added to x86 CPUs with little public notice, starting with Intel's [[Ivy Bridge (microarchitecture)|Ivy Bridge]] architecture and compatible Zen 2 AMD CPUs. It is implemented as a set of [[model-specific register]]s and is useful for [[machine check exception]] handling.<ref>
{{cite web
 |url=https://www.phoronix.com/scan.php?page=news_item&px=AMD-PPIN-Processor-ID-Linux
 |title=AMD Plumbing Linux Support For Reading the CPU's Protected Processor Identification Number (PPIN)
 |last=Larabel
 |first=Michael
 |date=March 19, 2020
 |website=Phoronix
 |access-date=March 20, 2020
}}
</ref>