Editing Slot 1 (section)

== General ==
With the introduction of the Pentium II CPU, the need for greater access for testing had made the transition from socket to slot necessary.  Previously with the [[Pentium Pro]], Intel had combined processor and cache dies in the same [[Socket 8]] package.  These were connected by a full-speed bus, resulting in significant performance benefits.  Unfortunately, this method required that the two components be bonded together early in the production process, before testing was possible.  As a result, a single, tiny flaw in either die made it necessary to discard the entire assembly, causing low production yield and high cost.{{citation needed|date=November 2020}}<!--please don't use other Wikipedia articles as references-->

Intel subsequently designed a circuit board where the CPU and cache remained closely integrated, but were mounted on a [[printed circuit board]], called a Single-Edged Contact Cartridge (SECC). The CPU and cache could be tested separately, before final assembly into a package, reducing cost and making the CPU more attractive to markets other than that of high-end servers. These cards could also be easily plugged into a Slot 1, thereby eliminating the chance for pins of a typical CPU to be bent or broken when installing in a socket.

[[File:AMD Slot A (left) and Intel Slot 1 (right)-flickr - by - flickrsven.jpg|thumb|A Slot A CPU on the left compared to a Slot 1 CPU (connector rotated by 180 degrees)]]

The form factor used for Slot 1 was a 5-inch-long, 242-contact [[edge connector]] named SC242. To prevent the cartridge from being inserted the wrong way, the slot was keyed to allow installation in only one direction. The SC242 was later used for AMD's [[Slot A]] as well, and while the two slots were identical mechanically, they were electrically incompatible. To discourage Slot A users from trying to install a Slot 1 CPU, the connector was rotated 180 degrees on Slot A motherboards. This also allowed motherboard manufacturers to save costs by stocking the same part for both Slot 1 and Slot A assemblies.

With the new Slot 1, Intel added support for [[symmetric multiprocessing]] (SMP). A maximum of two Pentium II or Pentium III CPUs can be used in a dual slot motherboard. The Celeron does not have official SMP support.

There are also converter cards, known as [[Slotket]]s, which hold a [[Socket 8]] so that a [[Pentium Pro]] CPU can be used with Slot 1 motherboards.<ref>{{cite web |url=http://usenet.p2preactor.com/index-t-1246309.html |archive-url=https://web.archive.org/web/20070929055735/http://usenet.p2preactor.com/index-t-1246309.html |url-status=dead |archivedate=2007-09-29 |title=PPro on a BX?-Usenet Gateway }}</ref> These specific converters, however, are rare. Another kind of slotket allows using a Socket 370 CPU in a Slot 1. These are generally more common than Socket 8 to Slot<ref>{{Cite web |url=https://slexus.com/ |title=Archived copy |access-date=2024-04-04 |archive-date=2024-04-03 |archive-url=https://web.archive.org/web/20240403130850/https://slexus.com/ |url-status=dead }}</ref> 1 slotkets. Many of these latter devices are equipped with their own voltage regulator modules, in order to supply the new CPU with a lower core voltage, which the motherboard would not otherwise allow.