There are many components of a laptop computer that are very different than their desktop PC counterparts. In this video, you’ll learn about the differences in keyboards, laptop storage, memory, LCD screens, power options, CPUs, and more.
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One thing you’ll notice very quickly when moving from a desktop computer to a laptop computer is that the keyboards are very different. We obviously don’t have as much room on a laptop as we have on the top of a desk, so the keyboards are much closer together, and a number of the keys that you’re accustomed to seeing may not be on a laptop computer. Here’s a good example of this. You can see that the keys look very similar in their layout.
Some things are very close together, such as these arrow keys at the bottom right, that are right next to the Control key and just under the Shift key. On this particular laptop, there’s not a numeric keypad, but even if there was, you wouldn’t have that cluster of keys that you normally see, with the Home key or end key, because there’s simply not enough real estate to be able to fit it onto a laptop.
The storage devices on laptop computers are also smaller than what you would find on a desktop. We see this very often with SSD, or solid state drives, inside of our laptop computers. These have no moving parts at all, so you don’t have the latency that you have with a traditional spinning hard drive. You’ll often find SSDs in a 2.5 inch and a 1.8 inch form factor. Another type of storage device you might find is a hybrid drive. You may see this referred to as an SSHD. That stands for solid state hybrid drive.
This has both flash memory and a traditional spinning magnetic hard drive, combined within the same unit. You have a hard drive that stores and saves the data that you’re using on this device, and it also has the SSD for very fast access of data that might be cached on that drive. And of course, we still have the magnetic disc technology that has these spinning drives inside of this case, just in the smaller 2.5 inch form factor that fits nicely in a laptop computer.
Another difference you’ll find between desktop computers and laptop computers is the type of memory that they use. We still have the same capacities that you would traditionally find in a laptop versus a desktop computer. But the physical size of the memory is very different. A good example of this is the SO-DIMM and the Micro-DIMM sizes. You can see that these are significantly smaller than the traditional full size DIMM that you might have in a desktop computer.
Because laptops are so mobile, they often will leave the facility and travel around to wherever their user might go. So to make sure that the appropriate user has access to the information that’s on that device, you may go a little bit farther than simpler requiring a simple username and a password. Many laptops include hardware built in for smart cards. These smart card readers are part of the laptop themselves. So you can take your smart card, slide it into the laptop, and then provide the credentials to make sure that the username, password, and some type of physical piece of information is all connected together for authentication.
If your laptop doesn’t have a smart card reader, you might want to consider using an external smart card reader. There are many available that will connect to the USB port that’s on a laptop computer. As our laptops have gotten smaller and smaller, we found that the optical drives are too big to fit into our very small laptop computers. So very often, we’ll have a removable or external drive that will connect to a USB interface on that device. If it is a larger laptop, it might still have an optical drive built into the side, just like you see here. And often, these cannot only read information from these optical discs; they can also be used to write information to a DVD or a CD-ROM, as well.
Our desktop computers are usually sitting in one place, and we very often will plug a wired ethernet connection in, because we know that that desktop computer is not going to move around. But of course, a laptop computer is very mobile, and will very often need to have a wireless card or wireless adapter connected somewhere on our laptop computer. This is a view from the back of one of my laptops.
You remove a cover, and you have an open space where you can install a wireless card into this mini PCI slot. You can see that this PCI Express slot is available to install the card. And in this laptop, they’ve already run the antenna wires directly to this interface, so that you’re able to install the card and then connect on the wires directly to the antenna leads on the adapter itself. This is a view just before installing the card, where you’ve placed it into the slot, and then you would push down to make it flat like everything else in the laptop, and it snaps in place. And then you can simply add on the antenna wires, once you’ve installed the adapter.
You’ll generally find two different kinds of form factors for these adapter cards. We were just looking at the Mini PCI adapter that you see here, but you might also find the smaller and much newer Mini PCI Express adapter size that you can see right here. The LCD displays that we might use on our desktop computer are very similar to the ones that we might have on a laptop, albeit a little bit smaller. They’re very light displays, and they provide a high resolution output to the information that’s on our laptop.
But of course, these are very fragile, and our laptops are constantly in motion, so we have to be very careful about not causing any damage to those LCD displays. We want to make sure we have a good case to put this laptop in. The resolutions on these LCD displays is fixed, just as the LCD displays are that you might get for your desktop computer, so you often want to make sure that you’re setting the resolution on your laptop to match the native resolution of the LCD display. That way, the information that you’re seeing on your laptop screen will be as clear and crisp as possible.
On our desktop computers, we have power supplies that are inside the case of our desktop computer, that plug into the wall outlet and take that AC power and convert it to DC power that our desktop computers can use. But of course, on a laptop, we don’t have a lot of room inside of our laptop cases. So that conversion process is done with an external AC adapter. You can see an example of one that’s right here. This adapter is responsible for taking the AC power from the wall and converting it to DC that you will then use when you plug into your laptop computer.
Generally, these devices are auto-switching, although the laptop you might have might be a fixed input AC adapter. And you’ll want to look at the specifications for your AC adapter, to see exactly what type of input it requires. On the other side of the AC adapter is a DC jack that is on the laptop, and this is usually a fixed and often proprietary connector, so you want to make sure you have exactly the right AC adapter for the laptop that you’re using.
The power adapter for my laptop computer is one that’s auto-switching. And I know this because, on the AC adapter, it says input, and it has 100-240 volts, and you can see the squiggly line right next to it, referring to AC. So I know that it will support either a 100 to 240 volt, and that works in pretty much every country. This also supports 50 or 60 Hertz of frequency, which also spans the range wherever I might go, and requires 2.0 amps of input. The output is going to be 19.5 of DC. There’s your DC symbol, and it is outputting 4.62 amps.
You will also see these symbols on your AC power supply, that have a plus and a minus. And then in the middle, it has a representation of the DC jack that’s on your laptop. In this particular case, it’s telling me that the positive polarity is on the inside of that jack, and the negative is on the outside. There should be a symbol on the device you’re connecting to that looks very similar. In fact, it should match exactly these polarities. That way, you can be assured that you’re using exactly the right interface for your laptop.
Through the years, we’ve used many different battery technologies to power our mobile devices. But these days, we generally will see lithium ion batteries in use. You’ll see these abbreviated as Li-ion. These are very common in our laptops and other mobile devices. Our lithium ion batteries don’t suffer from the memory effect that we saw with older battery technologies. In those older technologies, if you discharged the battery halfway, and then charged it back up, the battery would remember that it was only discharged halfway, and would only allow you to use that much of the battery. That was obviously a big disadvantage of those battery technologies that we no longer have with lithium ion.
One disadvantage of lithium ion, however, is that the more you recharge the battery, the more it will diminish the overall capacity of that battery. So we can still use the entire capacity of a battery, but as the battery is used over and over and over again, it begins to lose the capability to be charged. And eventually, it won’t be charged at all. So eventually, you will have to replace the lithium batteries that are being used for your laptop. You do want to make sure that the batteries that you use are going to match the laptop that you’re using. Because as you can see here, the different styles and types of batteries come in many different forms, and it’s usually a proprietary form factor that fits specifically in your laptop.
With a laptop, we often don’t have a big desk to be able to use, so we need some way to move the mouse around without having an external mouse. And so you’ll find, on most laptops, there’s a touchpad built right into the hand rest. That way, you can use the touch pad with your finger, to move the cursor around the screen or to be able to click on the items on your desktop. That way, you won’t need an external mouse to be able do exactly the same thing with this touchpad. Some laptops even have a pointing stick that’s right in the middle of the keyboard, instead of having a separate touchpad. That way, you’re able to have a much smaller place to be able to still move that cursor around the screen.
Our desktop computers are relatively large and heavy compared to a laptop. And that’s, of course, because we want the laptop to be very mobile. You’ll find many laptops have a plastic frame around them. This is made of heavy duty plastic, it’s very durable, it’s very difficult to break. But if you do manage to nick or break any part of this frame, it’s very inexpensive and easy to replace a section of that plastic frame. For ultimate durability, your laptop frame might be made of metal. This metal frame is a bit heavier, and it can also be more difficult to replace. If you do need to swap out a metal frame, you’re usually replacing a larger area, and so that can be a little bit more difficult, and a little more expensive to repair.
It’s very common to see external speakers being used with a desktop computer, but we don’t have that luxury on a laptop. So our speakers are usually built into the laptop itself. Because these are so small, they don’t usually have the highest quality available, but they do allow us to hear what’s going on. And often, the laptop may even have two speakers, so that you can at least get stereo sound out of these portable platforms.
Our desktop computers have very standardized motherboards. They’re exactly the same size, they’ll fit into exactly the same points inside of the desktop case, and that makes it very easy to swap them in and out. With laptops, however, the system board is very proprietary. It’s designed specifically for a model of laptop, and you can’t exchange different system boards between different laptop models. It might also be a bit more involved to swap a system board inside of a laptop, because you have more components connected to the system board at one time. Your CPU, your memory, your video adapter, and almost every other component might be integrated into this single system board.
The CPUs in a laptop are very different than the CPUs we might have on a desktop computer. They certainly operate the same, but there are features of these portable CPUs that are designed specifically for mobile environments. One good example is power management of mobile CPUs is very different, because it tries to keep the power down to a reasonable amount, so that you won’t use more power than necessary. It also minimizes the amount of heat that you might have inside of that laptop case.
Since we don’t have a lot of real estate on those system boards, it’s nice that the newer CPUs integrate even more capabilities. So a memory controller and video controller might also be integrated directly into your laptop CPU. This particular picture shows a CPU socket that is designed to be upgradable inside of a laptop. That’s not something that you normally find. Generally, when you’re purchasing a laptop, the CPU is something that is permanent to that system board, and it’s not something that you can easily swap in and out.
You’ll also find the laptop CPUs don’t quite have the horsepower that you might find in a desktop computer. With that extra room, we’re able to run much faster and much hotter, which is something you really can’t do inside of a laptop computer.