Although Wi-Fi is just about everywhere these days, desktop computers were not always designed with connecting wirelessly to the internet in mind. Because of this, there are situations where you may want to convert a desktop to wireless. Fortunately, there are simple solutions to this problem that don't involve buying a new computer or relying on an Ethernet cable. The simplest approach is to use a USB wireless adapter, but you might want to consider another option that works better: a PCIe Wi-Fi adapter.
Wi-Fi for Desktop: USB Adapters
Buying a USB Wi-Fi adapter is the simplest solution to convert a computer to wireless. The adapters are readily available, and the process doesn't require any particular tech know-how. Choose a USB wireless adapter from your favorite electronics store, ensuring that the adapter you buy is appropriate for the transfer speeds (measured in Mbps) of your router. There's no point in getting an adapter that's faster than your router. Ideally, you should get one that supports dual-band and offers USB 3.0 so that there isn't a speed bottleneck when transferring data to your PC.
Once you've chosen a USB Wi-Fi adapter, you insert it into an open USB port on your computer and install it. Most of the time, USB components install automatically, but there is a slight possibility that you may have to search on the manufacturer's website for the appropriate driver or install software on a disc that came with the adapter. From this point, you connect to the internet using the SSID and password for your router as you ordinarily would.
USB adapters are a great solution because of this simplicity, but it's important to note that the performance can be spotty sometimes. If you want a better solution, it's worth considering a PCIe adapter.
PCIe Wi-Fi Adapters
USB adapters are more of an off-hand fix than "converting" your desktop to wireless, If you want better performance while saving your USB ports for other connections, get a PCIe Wi-Fi adapter instead. These are small chips that plug into the motherboard of your computer and make it work just like a computer with Wi-Fi built-in from the start. Although installing one of these poses a greater challenge than installing a USB Wi-Fi adapter, it's worth it if you're looking for a more reliable solution.
Buy an appropriate PCIe Wi-Fi adapter, make sure your computer is turned off and unplugged, and open up the casing. You need to identify the motherboard of your computer – which is easy because it's big and the other components attach to it – and find the PCIe slots. There is usually a long PCIe slot for your computer's graphics card, with two (or more) smaller ones beside it, and these are aligned with the removable metal plates on the back of the computer. Remove the metal plate in line with the PCIe slot you want to use, which usually requires removing a couple of screws and then taking the plate away.
When you're done, push the PCIe adapter into the space and then remove the caps on the back of the card and install the antennae, which usually requires screwing them in place. When you switch your PC back on, the drivers should automatically install, but again you might need to download them manually from the manufacturer's website in limited cases.
Are There Other Solutions?
Unfortunately, short of getting a new computer, there are no other ways to convert your desktop computer to wireless. You can continue to connect with an Ethernet cable or use a laptop or other device for Wi-Fi, but the best solution is getting an adapter you feel comfortable installing.