Celeron is the budget, entry-level processor line made by Intel since 1998. Intel designed a wide range of Celeron processors for almost any socket that also runs a Pentium or Core processor. There are also some socket types specific to Celerons used in very old computers and certain laptops.
Slot 1
The original Celeron processors were designed for the Slot 1 motherboard connector. Unlike other socket types, a card with a processor built into it fit into a slot that looked similar to a memory slot. This technology, originally used by the Pentium II desktop processors, is also called a Single-Edge Cartridge. Slot 1 Celerons ran at 266 megahertz (MHz) to 433 MHz clock speeds.
PGA 370
The next Celeron slot type was the Pin-Grid Array 370. This looked similar to a PGA 478 socket except that it was bigger and had more empty space in its middle. There were 370 staggered pin holes in this socket. Celerons with the Mendocino and Coppermine cores used this socket, and they ran at 333 MHz to 533 MHz clock speeds.
PGA 478
Celeron processors using the Williamette and Northwood cores fit into the PGA 478 socket also used by most Pentium 4 models. The Celeron D series also used the PGA 478 socket, usually known as "socket 478" for short. Speeds for socket 478 Celerons ranged from 1.6 gigahertz (GHz) to 2.8 MHz, and bus speeds were at 400 MHz. The Celeron D ran up to 3.6 GHz clock speed and 533 MHz bus speed.
Socket 479
Celerons for laptops during the Pentium 4 era used a micro PGA 478 socket not compatible with regular desktop PGA 478 sockets. For this reason, they are called 479 despite having 478 pins. These processors were also called Celeron M and were an alternative to the Pentium M processors. Celeron M processors ran up to 2.5 GHz clock speeds and 400 MHz bus speeds.
LGA 775
The Land-Grid Array (LGA) 775 socket takes Celeron 400 series, Celeron D 300 series and the first Celeron Dual-Core processors. An LGA 775 socket was the first to use pins that touch contacts on the back of a processor, eliminating bent processor pins. The single-core LGA 775 Celeron processors ran up to 3.6 GHz clock speeds and 533 MHz bus speeds. The dual-core LGA 755 models ran up to 2.6 GHz per core for clock speed and had a maximum bus speed of 800 MHz.
Socket P
The Socket P is an update from the Socket 479. Like the Socket 479, Socket P has 478 pins but is not compatible with the old PGA 478 desktop standard. Compatible Celeron processors include Celeron M single-cores and Celeron Mobile dual-core processors up to 2.7 GHz in clock speed and 800 MHz in bus speed.
Sockets 1156 and 1366
Desktop celeron processors that are low-budget alternatives to the Core-i series use the flip-chip LGA 1156 and 1366 sockets. Celeron models for this socket include the 2.26 GHz clock speed dual-core G1101 and the single-core P1053 with a clock speed of 1.33 GHz and a bus speed of 800 MHz.
Tags: Celeron processors, clock speed, clock speeds, Celeron series, clock speed speed