Editing Pentium OverDrive (section)

==Socket 8==
{{Multiple image |total_width=250 |perrow=2
| image1   = Intel Pentium II OverDrive.jpg
| caption1 = Top view of the Intel Pentium II OverDrive CPU with [[heatsink]] and fan.
| image2   = Intel Pentium II Overdrive Engineering Sample.jpg
| caption2 = An [[engineering sample]] version of the Pentium II Overdrive, showing the bottom of the unit.
| image3   = KL Intel PPro Overdrive P6T Top.jpg
| caption3 = Pentium II Overdrive without heatsink. Flip-chip Deschutes core is on left. 512&nbsp;kB cache is on right.
}}

In 1998, the [[Pentium II#Deschutes (Pentium II Overdrive)|Pentium II OverDrive]], part number PODP66X333, was released as an upgrade path for [[Pentium Pro]] owners. Combining the [[Pentium II]] [[Pentium II#Deschutes (80523)|Deschutes]] core in a [[flip-chip]] package with a 512&nbsp;kB full-speed L2 cache chip from the [[Pentium II Xeon]] into a Socket 8-compatible module, this resulted in a 300 or 333&nbsp;MHz processor that could run on a 60 or 66&nbsp;MHz front side bus. This combination also brought together some of the more attractive aspects of the Pentium II and the Pentium II Xeon: MMX support/improved 16-bit performance and full-speed L2 cache respectively. This configuration would be replicated by the later "[[Pentium II#Dixon|Dixon]]" mobile Pentium II core with 256&nbsp;kB of full-speed cache embedded on-die, as well as the later "[[Pentium III#Coppermine|Coppermine]]" and "[[Pentium III#Tualatin|Tualatin]]" Pentium III cores using the same 256&nbsp;kB full-speed cache embedded on-die.

This upgrade could be used in single and dual processor [[Socket 8]] systems. It does not support quad (and even hexa) processor Socket 8 systems due to it lacking four-way or higher multiprocessing, however it can work in two sockets of quad processor Socket 8 systems with CPU 3 and 4 removed. Unofficially, it could also be run in quad and hexa processor Socket 8 systems. This came about after some users upgraded their ALR 6x6 systems with them.<ref>{{Cite web|url=https://arstechnica.com/civis/threads/re-my-custom-alr-6x6-is-now-finished.878654/|title=Re: My Custom ALR 6x6 is now FINISHED!!!!!!|date=December 5, 2001|website=Ars OpenForum}}</ref>

One of the major use cases for these chips was [[Intel]]'s [[ASCI Red]] supercomputer, stationed at [[Sandia National Laboratories]]. This supercomputer was the first computer to break the [[teraFLOPS]] performance mark in late 1996, which up until the upgrade was running dual Pentium Pro CPUs in its nodes since its inception. ASCI Red had all 4,510 CPUs upgraded from dual Pentium Pros to dual Pentium II Overdrives in 1999, making it the first computer to break over two [[teraFLOPS]] after the upgrade while further maintaining its position as the world's fastest on the [[TOP500]] list at the time since it held that position from its first full operations in 1997 up until late 2000, when it was surpassed by [[IBM]]'s [[ASCI White]], a supercomputer stationed at [[Lawrence Livermore National Laboratory]]. ASCI Red then continued to use dual Pentium II OverDrive CPUs for the remainder of its usage until it was finally decommissioned in 2006.

In Intel's "Family/Model/Stepping" scheme, the Pentium II OverDrive CPU is family 6, model 3. Despite being based on the Deschutes core, it identifies itself as a [[Pentium II#Klamath (80522)|Klamath]] Pentium II when queried by the [[CPUID]] command.<ref>{{cite web|url=http://www.heise.de/ct/english/98/18/020/|title=c't - English pages (18_98, page 20)|website=www.heise.de|first=Georg|last=Schnurer|archive-url=https://web.archive.org/web/19990914131901/http://www.heise.de/ct/english/98/18/020/|archive-date=September 14, 1999|access-date=April 12, 2009}}</ref> As noted in the Pentium II Processor update documentation from Intel, "although this processor has a CPUID of 163xh, it uses a Pentium II processor CPUID 065xh processor core."<ref>[http://download.intel.com/design/PentiumII/specupdt/24333749.pdf Specification Update for the Pentium II Processor, page 15, note 3<!-- Bot generated title -->] {{webarchive|url=https://web.archive.org/web/20110831012432/http://download.intel.com/design/PentiumII/specupdt/24333749.pdf |date=2011-08-31 }}</ref>