When buying a computer, one of the most important components in the computer is the WiFi (Wireless) Access Card. Also known as a WiFi card, Wireless Modem, Datacard, or Air-cards, the WiFi card is your connection to the outside world and the Internet. The better the card, the better your overall experience with your new computer.
When buying your laptop, you should confirm that the manufacturer states the WiFi radio has dual-band support in both 2.4 and 5 GHz radio frequencies or the specifications specifically include WiFi ac/a/n or 802.11 ac/a/n. The presence of the letter “a” indicates the radio operates in the 5 GHz frequency; this is the primary performance differentiator. Anything else will not be able to take full advantage of many of the latest wireless networks and their true network speed. Keep in mind, the 5GHz channel is much cleaner with less interference with 23 non-overlapping channels- 8 times more than 2.4GHz for transmission, which makes it suitable for applications like Video.
Unlike wired networks, which allow your computer to transmit and receive on a dedicated private copper cable, your Wi-Fi radio must transmit over-the-air using a shared radio frequency. In plain terms, your wireless transmissions share the same radio frequency with other wireless devices trying to transmit data at the same time. Effectively, only one transmission can take place at a time in a given radio channel. Wi-Fi radios limited to working in the 2.4 GHz frequency support only three non-overlapping radio channels. In comparison, radios operating in the 5 GHz radio frequency support over 23 non-overlapping radio channels.
If your laptop only supports this single frequency, it must compete among the three available radio channels with hundreds of Apple iPhones, Comcast Xfinity Wireless, Wireless Philadelphia, and many other foreign networks that operate exclusively in the 2.4 GHz frequency. If you want to avoid this radio frequency competition, you need a dual-frequency WiFi card.
If you are not sure if the computer you are considering has a single-band or dual-band WiFi (Wireless) Card, look under the laptop’s wireless device/Wi-Fi card specifications on the box, label, or product webpage. WiFi card information and details should be listed under the “Communications” section and the WLAN category of the technical specifications of the computer.
NOTE: Apple laptops are sold exclusively with dual-band Wi-Fi radios, so there are no Wi-Fi configurations to check at purchase time.