Socket 479

Socket 479

Type	PGA-ZIF
Chip form factors	Flip-chip pin grid array (FC-PGA2)
Contacts	479 on the socket, 478 or 479 pins on the processor, 478 contacts used
FSB protocol	AGTL+
FSB frequency	400 MT/s, 533 MT/s
Processors	Intel Pentium M Intel Celeron M VIA C7-M
Predecessor	Socket 495
Successor	Socket M
This article is part of the CPU socket series

Socket 479 (mPGA479M) is a CPU socket used by some Intel microprocessors. It is the socket used by the Pentium M and Celeron M mobile processors normally used in laptops,^[1] but has also been used with Tualatin-M Pentium III processors. The official naming by Intel is μFCPGA and μPGA479M.

There exist multiple electrically incompatible, but mechanically compatible processor families that are available in PGA packages using this socket or variants thereof:^[1]

• Socket 478 for Pentium 4 and Celeron series desktop CPUs;
• Socket 479 for Pentium III-M (released in 2001);
• Socket 479 for Pentium M and Celeron M 3xx (this was the most common version of the socket, and was released in 2003);
• Socket M for Intel Core, Core 2 and Celeron M 4xx and 5xx processors; and
• Socket P for Core 2 processors.

Even the Intel's CPU specifications seem to be not clear enough on the distinction and instead use the package/socket designations PGA478 or PPGA478 for more than 1 of the above sockets.^[2][3]

Perhaps adding yet more confusion, some of the PGA-based CPUs above are also available in a BGA (or more precisely, μBGA or even μFCBGA) package which has all of the 479 contacts (balls) populated. For these CPU variants, the Intel's CPU specifications use the designations BGA479,^[2] PBGA479^[3] or H-PBGA479.^[4] It should be however pointed out that these designations denote rather the CPU package itself and not the socket, which the BGA variants do not use at all (they are intended to be directly soldered to the mainboard, e.g. in an embedded system). The non-BGA counterparts of these CPUs use any one of the above mentioned sockets, not only the Socket 479.