Assignment #4

CPU Socket From Wikipedia, the free encyclopediaJump to: navigation, searchThe Socket 370 processor socket, a ZIF type PGA socketA CPU socket or CPU slot is a connector on a computer's motherboard that accepts a CPU and forms an electrical interface with it. As of 2007, most desktop and server computers, particularly those based on the Intel x86 architecture, include socketed processors.Most CPU-sockets interfaces are based on the pin grid array (PGA) architecture, in which short, stiff pins on the underside of the processor package mate with holes in the socket. To minimize the risk of bent pins, zero insertion force (ZIF) sockets allow the processor to be inserted without any resistance, then grip the pins firmly to ensure a reliable contact after a lever is flipped.As of 2007, several current and upcoming socket designs use land grid array (LGA) technology instead. In this design, it is the socket which contains pins. The pins contact pads or lands on the bottom of the processor package.In the late 1990s, many x86 processors fit into slots, rather than sockets. CPU slots are single-edged connectors similar to expansion slots, into which a PCB holding a processor is inserted. Slotted CPU packages offered two advantages: L2 cache memory could be upgraded by installing an additional chip onto the processor PCB, and processor insertion and removal was often easier. However, slotted packages require longer traces between the CPU and chipset, and therefore became unsuitable as clock speeds passed 500 MHz. Slots were abandoned with the introduction of AMD's Socket A and Intel's Socket 370.

PGA Package Type

PGA is short for Pin Grid Array, and these processors have pins that are inserted into a socket. To improve thermal conductivity, the PGA uses a nickel plated copper heat slug on top of the processor. The pins on the bottom of the chip are staggered. In addition, the pins are arranged in a way that the processor can only be inserted one way into the socket. The PGA package is used by the Intel Xeon™ processor, which has 603 pins.

FC-PGA Package Type

The FC-PGA package is short for flip chip pin grid array, which have pins that are inserted into a socket. These chips are turned upside down so that the die or the part of the processor that makes up the computer chip is exposed on the top of the processor. By having the die exposed allows the thermal solution can be applied directly to the die, which allows for more efficient cooling of the chip. To enhance the performance of the package by decoupling the power and ground signals, FC-PGA processors have discrete capacitors and resistors on the bottom of the processor, in the capacitor placement area (center of processor). The pins on the bottom of the chip are staggered. In addition, the pins are arranged in a way that the processor can only be inserted one way into the socket. The FC-PGA package is used in Pentium® III and Intel® Celeron® processors, which use 370 pins.Pentium III and Intel® Celeron®

FC-PGA2 Package Type

FC-PGA2 packages are similar to the FC-PGA package type, except these processors also have an Integrated Heat Sink (IHS). The integrated heat sink is attached directly to the die of the processor during manufacturing. Since the IHS makes a good thermal contact with the die and it offers a larger surface area for better heat dissipation, it can significantly increase thermal conductivity. The FC-PGA2 package is used in Pentium III and Intel Celeron processor (370 pins) and the Pentium 4 processor (478 pins).

S.E.C.C Package Type

S.E.C.C. is short for Single Edge Contact Cartridge. To connect to the motherboard, the processor is inserted into a slot. Instead of having pins, it uses goldfinger contacts, which the processor uses to carry its signals back and forth. The S.E.C.C. is covered with a metal shell that covers the top of the entire cartridge assembly. The back of the cartridge is a thermal plate that acts as a heatsink. Inside the S.E.C.C., most processors have a printed circuit board called the substrate that links together the processor, the L2 cache and the bus termination circuits. The S.E.C.C. package was used in the Intel Pentium II processors, which have 242 contacts and the Pentium® II Xeon™ and Pentium III Xeon processors, which have 330 contacts.

S.E.C.C 2 Package Type

The S.E.C.C.2 package is similar to the S.E.C.C. package except the S.E.C.C.2 uses less casing and does not include the thermal plate. The S.E.C.C.2 package was used in some later versions of the Pentium II processorand Pentium III processor (242 contacts

OOl Package Type

OOI is short for OLGA. OLGA stands for Organic Land Grid Array. The OLGA chips also use a flip chip design, where the processor is attached to the substrate face-down for better signal integrity, more efficient heat removal and lower inductance. The OOI then has an Integrated Heat Spreader (IHS) that helps heatsink dissipation to a properly attached fan heatsink. The OOI is used by the Pentium 4 processor, which has 423 pins.