Currently, computers are truly complete, with great connectivity and capabilities. But, the first computers were much simpler and needed additional elements to connect peripherals or expand their capabilities. This was achieved through the expansion slotswhich allowed (and allow) add cards that allowed, among others, to connect speakers or connect to the original internet.
We have become accustomed to a motherboard having many USB ports, Ethernet port, audio connectors and even video outputs. All these elements, common today, were once something rather “strange.”
Although there is great integration of elements on the motherboard, the expansion slots are still very important. One of the most common components that uses this connection element is graphics cards. Let’s take a look at its origin and characteristics, as well as the typologies.
Why are they called expansion slots?
As its name indicates, it is used to add functions or capabilities to computers. Depending on their characteristics and construction, they allow adding additional peripheral devices, such as monitors, printers or joysticks. They also allow you to add capabilities, such as internet connection.
You should know that expansion slots can have other names, such as expansion slot or socket.
Expansion cards are connect directly to the motherboard through specific connectors. These connectors usually communicate directly with the processor, although this is not always the case. Some of the expansion slots may be connected to the chipset.
These connectors have concrete and standardized dimensions. This is intended to prevent manufacturers from creating their own solutions and limiting the freedom of choice of users. In addition, creating standardized solutions saves development and manufacturing costs for expansion card creators.
You must know that the importance of expansion slots has been declining. Currently, the sound card, internet card or USB ports are integrated into the motherboard. Despite everything, there are still different types of expansion cards, the most important being graphics cards.
What types are there
Like any other component, expansion slots have evolved and been adjusted. They have been adapted to the different needs of the time and existing technologies. Some of these connectors, now obsolete and disused, are:
- ISA: Created by IBM in 1981, it is the first expansion slot created for a computer, specifically, for the IBM PC.
- PCI: They replaced the ISA slot. Allows you to connect peripherals directly to the motherboard, such as sound or network cards. Parallelization is introduced, which improves performance
- PCI-X: It is a variant of PCI that was created for servers and workstations. It provided greater bandwidth, operated at a frequency of 66 MHz and a 64-bit bus.
- AGP: Specific port for graphics cards that allowed a direct connection between the graphics card and the memory. It was an Intel solution to correct the bottlenecks that graphics had with the PCI bus
All of these ports no longer exist, they have been replaced by a single type of connector. We talk about the slots PCI Expressalso called PCIe.
This type of expansion slots replaced all the previous ones, being a unique and standardized solution. It is characterized by being a simple solution to design and build.
PCIe slots have different versions that add different features, the most recent being PCIe 4.0 and PCIe 5.0. Within this type of slot we find different sizes, such as: x16, x8, x4, x2 and x1. What they tell us is the number of threads or “roads” of communication with the processor.
Inside here we can add a variant such as PCIe M.2 slots. Primarily, these types of slots are used for SSD drives, which offer high transfer speeds. These slots can also be used to install wireless network cards.
