126: Laptop & Desktop Ports Explained – What do all the sockets do?

Hey there do-it-yourself technicians. Are you confused by all of the ports and plugs that are available on your new laptop or desktop?

In this video, we’ll go through more than a dozen of the most common connectors on laptops and desktops and let you know what they’re for.

So you’ve got a new device and you’re not sure what all of the sockets on the side or the back do. Well, here’s a step-by-step run-through of all those different plugs and what you might use them for.

The most common is USB. We all recognize a USB-A socket and the plethora of devices that we can plug into it. we actually have a full episode on USB and what the various colours sockets and speeds are and that’s linked up here.

USB-C is the newest and fastest incarnation of the USB family and notable for also being the power connector on many laptops.

The power connector is a tricky one if it’s not USB-C. It could look like just about anything. There’s rectangle ones and round ones and probably even some square ones out there. It’s hard to show you them all, but I do have this collection of plugs up here that came with one of the aftermarket chargers that I bought that will charge multiple different devices, and that’s just some of them. A lot of the newer ones are getting smaller and smaller as they cope with thinner and thinner laptops.

On the video side, we have HDMI, mini HDMI and micro HDMI. A HDMI connector is probably familiar to anyone who’s plugged in a TV in the last 10 years. Mini and micro are less common. The only mini HDMI connector that I have is on this camera that is recording this episode, but I’m sure they will become more and more common, particularly as laptops get thinner and thinner. Many desktop video cards will also have HDMI ports. One other great feature of HDMI is that it can also carry audio such as you would into your TV and use the TV’s internal speakers. You can do the same from your laptop or desktop. It can carry audio to whatever is displaying the video as well.

VGA and DVI ports are relatively unusual these days on a laptop but still quite common on desktops. DVI less, so the main reason for this is the plugs are simply too big to fit on a laptop. Again the VGA connector is 15 pins arranged in three rows, usually with a blue backing which you plug in a blue-headed cable. The DVI connector is both an analog and a digital connector and uses up to 29 pins to carry the information in some of its various forms. The DisplayPort connector has this very distinctive L-shape internal and, like DVI and VGA, carry video only.

The mini Display Port connector, also known as Thunderbolt, is another multi-function interface, in many ways the precursor to USB-C. It can carry video, power and also be used for network and storage, with up to six devices daisy-chained per port.

SD Card and micro SD Card readers are common on laptops these days and in desktops, often combined with other types of cards like MMC and XD cards, usually in an array that looks like this. You can also buy USB-A and USB-C card readers that will plug into laptops or desktops alike.

Ethernet ports are becoming less and less common in laptops as they get thinner and thinner, but they’re still ubiquitous on desktop machines. My Lenovo Yoga L390 has a dedicated mini rj45 connector for networking because it’s just too thin to hold a standard rj45, but this requires an optional dongle. Honestly, I would much prefer if they’ve taken that out and put in another USB-C connector. When I need wired ethernet, I plug in either a USB-A or a USB-C to ethernet adapter and use that. There’s no way I can justify the extra plug that won’t be useful on any other laptop.
Headphones and microphones. Sometimes these are separate ports, sometimes they’re together, and it can get a little bit confusing when you’re trying to plug either a headset or a microphone or headphones in. If it’s just the single port, It’s almost always a headset and will take something similar to what you might use on a mobile phone. If there are two ports, then you can simply plug a microphone into one and headphones into the other, and they’ll usually be labelled for that.

E-SATA is an external version of the SATA connection that is used inside the computer for storage devices. Not very common these days because USB is just fast enough for those sorts of connections and much more widely available. Some devices actually combine an e-SATA and a USB port into one, which is a really nifty use of the technology and the space.

The PCI-Express card slot is just about gone for good. I would say it was used to add ethernet, wi-fi, card readers, 4g connection, those sorts of things in laptops before they were built-in, and these days USB-C does basically exactly the same job for anything that needs it. It’s certainly fast enough to transfer data for just about anything.

The last port that actually confuses some people is known as the Kensington lock. This is designed to plug in a lock, either a key lock or a combination lock that you then anchor to the desk that your computer is on. This is basically just to make it more theft-proof. they won’t stop a determined thief, but they will provide a visual cue and slow down any would-be thieves.

Question of the day. Did you know all of those ports? Is there some that I missed? Let me know in the comments down below and while you’re there, leave a thumbs up if this was useful for you.

The Tech Doctor exists to help you become your own technician, Learn about the technology, Protect yourself from the bad guys and Repair it if it breaks.

Thank you so much for watching, and I’ll see you on the next episode. Have a great day.