What is an I/O card?
An I/O card is a type of computer card which can be inserted into a slot inside your computer to provide you with additional functionality. I/O stands for “input/output” and refers to the ability of the cards to allow extra devices or connections to be plugged in. I/O cards are also commonly known as expansion cards and include network or LAN cards, SAN cards and modems.

‘Ё‘ЁDo I need one?
‘ЁMost computers come with a number of I/O cards already installed, including a LAN/modem card for high speed internet connectivity and graphics or sound cards. However, you may want to upgrade your computer or add extra ports and slots to plug in different devices, in which case you’ll probably need to replace your current I/O cards or buy additional ones. Keep in mind that computers only come with a set number of I/O card slots (known as expansion slots) which limit the number of cards you can have installed at any one time.

What do I need to look out for in an I/O card?
‘ЁThere are a few essentials you need to check before buying any I/O card so that you know it’ll work with your computer and provide you with what you need. First, you’ll need to check what sort of expansion slots you have in your computer. These can include slots like PCI, PCI Express and AGP, as well as a host of other acronyms and confusing terms which you may not remember or know. If you’re not sure about what sort of slots your computer has, you should either check the manual or bring in your computer to a store to find out. Buying an I/O card which doesn’t match your computer’s expansion slot is an error you can’t make right: get the type of slot right, and you’ll be set to install.‘Ё‘ЁYou should also check how much power the I/O card will consume and whether your computer will be able to provide that power. While this isn’t usually an issue with low-power LAN cards and networking cards, many I/O cards (particularly audio and video cards) use up a lot of power, which can lead to you burning out your system if you’re not careful. Check the voltage and load of your power supply and make sure you can sustain the extra card before you buy, or consult a technician beforehand.‘Ё‘ЁSome I/O cards aren’t compatible with certain operating systems, so make sure you consult the box before you make a purchase.

‘Ё‘ЁWhat about price?
‘ЁDepending on the function of the I/O card, prices can vary from a few dollars to the thousands. The best cards of all types will command price premiums, but you’ll be getting far stronger functionality and stability - for the most part. However, many “generic” I/O cards are available which provide the power of big-name brands without the brand itself - they’re usually variants on the higher-end cards which are made by the same manufacturers to cater for more savvy buyers. Shopping around and comparing prices is, as always, a good move, especially since the I/O card market is extremely competitive. Make sure you get a warranty, and remember that the most expensive card may not be the one you actually need. Happy hunting!