Cpu chip pin grid

CPU chip with pin grid array (PGA): the golden pins that connect the processor to the motherboard and their technological evolution.

About this subject

The pin grid array (PGA) is a type of CPU package where connection pins are arranged in a square grid on the underside of the chip. This configuration allows a high number of contacts in a compact space, essential for modern processors with hundreds or thousands of connections. Historically, AMD used PGA for many years in sockets like AM3+ and AM4, while Intel moved to land grid array (LGA), where pins are on the motherboard socket. However, PGA remains common in low-cost processors and some embedded systems.

The pin layout follows a specific pattern defined by each manufacturer. For example, an AM4 processor may have 940 pins, while AMD's TR4 socket supports up to 4094 pins. The pins are usually gold-plated to prevent corrosion and ensure good conductivity. Correct alignment is ensured by a chamfer at one corner of the chip. A broken pin can render the processor unusable, posing a risk during handling.

The evolution of PGA has accompanied the growing demand for power and bandwidth. Older processors like the Pentium used PGA with fewer than 300 pins. Modern Threadripper chips use dense arrays that require robust mechanical sockets. A curiosity is that the square or rectangular grid shape optimizes trace routing on the motherboard, facilitating multi-layer PCB design.

Frequently Asked Questions

What does PGA mean in CPUs?

PGA stands for Pin Grid Array, a package type where the connection pins are on the processor, which fits into a socket with holes on the motherboard.

What is the difference between PGA and LGA?

In PGA, the pins are on the CPU. In LGA (Land Grid Array), the pins are on the motherboard socket, and the chip has flat contacts. LGA reduces the risk of damaging processor pins.

Is it true that CPU pins break easily?

Yes, the pins are fragile. Careless handling or incorrect insertion can bend or break pins, ruining the processor. Care is recommended when installing or removing PGA processors.