How It Works: Peripherals

How It Works: Peripherals

by Dustin Sklavos

It’s been a long time coming, but this is one of the articles I’ve actually really been looking forward to. The parts I’ve covered before this are typically the kinds of things you’d expect to see covered on the product page, but you usually have to closely read the specifications sheet to actually get any of this information. That’s a shame, too, because the expandability of the modern notebook is exactly the kind of thing that gives it potential as not just a mobile computer, but as a fully-fledged machine capable of multimedia and enterprise work as well.

One of the nice things about this chapter is that it’s actually pretty simple compared to its predecessors. We aren’t talking about majorly confusing stuff here; each of the ports on your laptop has a largelydistinct purpose. So today, I’m going to cover one of the more exciting andenjoyable things about owning a laptop: hooking stuff up to it.

How It Works: Peripherals

As I mentioned in the introduction, laptop ports are, at this juncture, fairly specific in their purpose. A good notebook is going to be pretty fully-featured and cover all of these bases.

So what are these bases? The major ports on a modern notebook are the USB ports, the FireWire port, the eSATA port, the card readers, the video output ports, the ExpressCard, and the old and now rarefied stalwart, the PC Card.

There are certain ports I’ve omitted, because unlike the rest of these, these omissions should be fairly obvious in function: the power jack and the speaker/headphone/microphone jacks. I think we need to be realistic here; there’s nothing I can tell you about any of these, but if you don’t know how to identify them or what they do, consumer electronics not be for you. The only other omission I’ve made is in the form of proprietary expansion ports; there isn’t a whole lot I can say about these, they’re specifically designed to interface with the manufacturer’s docking devices.

There isn’t a whole lot to say in advance of this port breakdown, so we’ll just get started.

USB (Universal Serial Bus)

The USB port, or Universal Serial Bus, is designed to basically be a sort of peripheral catch-all. The word Universal isn’t to be taken lightly; these ports can handle just about anything. Flash drives plug into these, along with external hard drives, external disc drives, printers, scanners, mice, keyboards, game controllers … there are even USB-connected boxes that can be used to drive extra monitors.

USB ports are identifiable as thin, rectangular ports on your laptop (or desktop), sometimes clustered together or stacked one on top of the other. Presently there are two specs currently in circulation: USB 1.1 and USB 2.0. USB 1.1 operates at a maximum speed of 12Mbit/s, which is extremely slow. USB 2.0 bumps that speed up to 480 Mbit/s, vastly improving USB as a means of transferring large amounts of data to flash drives and external hard drives.

Another major benefit of USB is that the ports themselves are powered, which means peripherals can draw power directly from the system. If the device doesn’t require too much power, it can operate without being plugged in: this is why your flash drive works, why your external mouse works, and so on.

Finally, USB ports can be split with what are called USB hubs. These are basically units that you can connect to a single port that spider out into multiple ports. So if your laptop only has two USB ports, you can connect a hub to substantially increase the number. You’re still dealing with that limited bandwidth and power output, but if you’re only connecting say, a mouse, a keyboard, and a printer … well, the printer’s going to be operating off of its own power anyhow, so you should be fine. External hard disks, on the other hand, should generally not be used with hubs and instead be given their own independent port to maximize the bandwidth available to them.

And this is the limitation of USB: for how flexible it is, it’s not very good for transfers that require a great deal of data to be transferred at a high speed. External hard disks will typically find themselves throttled by the bandwidth of USB.

Still, USB is the most common port you’re going to find on laptops and the best means of expanding their utility.

FireWire (IEEE1394)

Some people are probably going to wonder why I put this second, but there’s a good reason: I’m a film student! (Well, not anymore, graduated as of the end of !) FireWire used to be the port of choice for external hard drives and even direct computer-to-computer networking in some cases, but use of it is now reserved almost exclusively for digital video, and it remains the best suited interface for digital camcorders.

There are two different port types for FireWire: 4-pin and 6-pin. 4-pin is the most commonly seen on laptops, although 6-pins tend to show up on Macs. The 4-pin is a very small, long U-shaped port, while the 6-pin looks like a slender trapezoid. Drawn freehand like a former professor made the mistake of doing, it can look decidedly phallic. The only difference between the two is that the 6-pin can also provide power through the port, but given how rarefied FireWire devices requiring host power have become, this isn’t really an issue.

The specification for conventional FireWire – the type you’re likely to run into – rates the bandwidth at 400Mbit/s. This is lower than USB 2.0, yet FireWire often outperforms it. Sometimes it’s not all pure bandwidth: USB has much more host system overhead than FireWire does. While USB tends to run off the motherboard chipset (covered back in part II for those who haven’t been following along), FireWire almost always has its own dedicated controller that offloads a lot of the processing. As a result, FireWire is more consistent and is ideal for capturing video from digital camcorders.

There is also the FireWire 800 standard which operates at 800Mbit/s, but this type of FireWire port is largely only seen on some Apple computers and a few expansion cards for desktops.


The eSATA standard is relatively new, but a very important one. The port hasn’t become ubiquitous the way USB has yet, but it’s showing up more and more frequently these days. Some manufacturers have even taken to implementing a combination USB/eSATA port on their laptops to save space and maximize flexibility.

There’s a very good reason why eSATA is proliferating.

If you think back to part VI when I talked about hard drives, you’ll remember that the interface commonly used for hard drives these days is Serial ATA, or SATA. What eSATA is, is an external version of that port. This is effectively allowing you to connect an external hard drive to the same amount of bandwidth the internal drives enjoy, typically a blistering 3Gbit/s, or approximately 3,000Mbit/s. This is surely more bandwidth than your average hard drive will need.

SATA (left) and eSATA (right) connectors

An eSATA port means being able to expand the storage of your laptop externally without having to sacrifice performance; indeed, a desktop class hard drive on an eSATA port could actually perform better than the internal laptop drive.

It’s not all bread and roses, though. In my experience, eSATA has been somewhat picky. Some eSATA controllers can handle hot-plugging – plugging the drive in while the computer is on – while others require the external drive to be connected and powered on when the computer boots up. The connectors – and connection consequently – also tend to be on the fragile side, prone to easily being removed from the port.

That said, if you’re looking to expand storage for your laptop and want all the performance you can get, it really doesn’t get any faster than this.

Video Output

There are basically four types of video output ports you can expect to see (or see in combination) on modern laptops. There’s S-Video, which you should be familiar with from your television set. There’s VGA (also called D-SUB), which is the trapezoidal 15-pin connector that’s been used for monitors for a long time now and tends to be color coded blue. There’s DVI, which is the current dominant connector for desktop monitors (though somewhat uncommon on laptops). And there’s HDMI, which is the big daddy that largely exists for you to connect your laptop to your television. Confused? Don’t be, it’s simple actually.

First, DVI and HDMI are actually based on the exact same protocols, and are interchangeable through the use of proper adaptors. The only major difference between the two is that an HDMI port can carry an audio signal while DVI cannot. HDMI cables also tend to be thinner and easier to connect than DVI. These two are also purely digital connections, so as a sidenote: Monster HDMI cable is snake oil. The cheap $10 cable at Fry’s will do just as good a job, because we’re not dealing with the quality of an analog signal here, we’re dealing with 1’s and 0’s. Analog signals allow for a lot of kinda; digital signals are strictly yes or no.

S-Video is an old standard, and its appearance on laptops really just exists as a means for them to connect to older tube-based televisions. S-Video is generally not going to be worth your time, but could be useful for some of you.

And finally, there’s VGA, or D-SUB, which is pretty much the standard every computer monitor will connect to this port. D-SUB produces an analog signal, but on lower resolution screens (typically 1680×1050 and lower), the picture tends to have a minimal difference compared to DVI or HDMI. It’s worth mentioning that most HDTVs produced these days do have a D-SUB port on the back, but if you’re going to connect your laptop to your HDTV, HDMI is likely going to be the way to go, since HDMI can carry sound in addition to picture.

This is also a good time to bring up HDCP, or High Definition Content Protection. If you’re planning on using your laptop to play Blu-ray discs on your HDTV (and that’s not a bad idea), you will DEFINITELY want to use the HDMI connection. HDCP operates over digital connections to ensure that you’re not trying to steal the precious movie from the MPAA through some kind of illicit and utterly convoluted means. Most if not all HDTVs produced these days support HDCP, and the same is true of the HDMI ports found on modern laptops. DVI connections also often support HDCP, since HDMI is just an extension of DVI.

Card Readers

I don’t want to get into this too much because honestly, this has gotten really convoluted. The flash memory cards used for phones and digital cameras are the kind of crap where an industry really needed to standardize on something and didn’t, which is how you get the 293748297392-in-1 USB card readers.

That said, the built-in card readers have, in my experience, at least always supported SD (Secure Digital) cards and the extensions thereof (MiniSD and MicroSD, with proper adaptor). These exist essentially to aid in copying images off of your digital camera instead of having to connect the camera itself, or alternatively, to copy files on to and off of the flash card you use in your cellular phone if your phone supports it.

While the majority of peripherals these days seem to be using Secure Digital (a visit to NewEgg’s digital camera section confirms as much), others use Compact Flash or xD; Compact Flash support tends to be hit and miss with laptops, while xD tends to show up a little more often due to the smaller size. And finally, just to make sure they couldn’t join the party without screwing everything up, Sony has a proprietary format they use and tried to push on an unwilling market like a drunken frat boy on a cheerleader: Memory Stick (including Memory Stick Pro, Memory Stick Duo, et al). The Memory Stick tends to be fairly commonly supported, and obviously you can expect it to be supported – with gusto – on every Sony laptop.


The ExpressCard slot is going to be one of the, if not the, largest slots on your laptop. ExpressCard comes in two flavors: ExpressCard/34 and ExpressCard/54. The only difference between these two is the physical size; the connector itself remains the same. ExpressCard/34 is 34mm wide; ExpressCard/54 is, oddly enough, 54mm wide.

ExpressCard is essentially for more complex peripherals, and can use either a single channel of PCI Express (see part II again) which supplies a healthy amount of bandwidth, or operate in a USB mode, supplying the same amount of bandwidth as a USB 2.0 port. ExpressCard is also powered, like USB ports.

This slot is used for more complex peripherals like sound hardware, TV tuners, and actually adding USB, FireWire, or eSATA ports. It does all of this in the form of the ExpressCard peripheral itself.

Unfortunately, I’ve found ExpressCard to have two major drawbacks. The first is that I’ve found ExpressCard/34 cards to oftentimes be somewhat wobbly in ports that can accommodate ExpressCard/54 (34s can be used in 54-sized ports, but not vice versa due to size). The second is the more unfortunate one; while the uptake of ExpressCard has improved somewhat over the past year, the number of peripherals available that use it are still not as numerous as you’d probably like. When it was introduced you’d be lucky to find any at all; now, they’re still competing for shelf space with …


This is the old stalwart that’s been supplanted by the new hotness that is ExpressCard. It’s been a while since I’ve seen a new laptop with a PCMCIA, or PC Card, port, but peripherals for this port are still pretty common since the standard itself has lived such a long and fruitful life.

This slot is going to be larger than the ExpressCard slot is, and will easily be the largest slot/port on your laptop. The peripheral PC Cards are roughly the size of a stack of about fifteen playing cards. This standard is slower and draws more power than the newer ExpressCard, but is extremely common on laptops prior to 2006 or 2007.


Hopefully by this point you’ve come to realize what function each of these ports can serve on your laptop. That said, a lot of laptops not necessarily provide all of these options, so you have to decide which you can and cannot live without.

As a general rule, you’ll want a laptop to have at least three USB ports, and spaced in some convenient fashion. Flash drives on keychains are basically the new floppy disk (for those of you who don’t know what a floppy disk is, ask your parents) and means of transferring data quickly, so it’s useful to have a USB port close to the front of the machine. On my old HP laptop, I had two USB ports, and they hung out right next to each other. This made me angry because I’d have a hard time connecting my external hard drive and my flash drive at the same time since one connector would always be somehow too fat to fit the other in. This is the kind of practicality you’re going to want to look for – not just a good number of ports, but a good spread.

FireWire is something you’re going to want to take or leave. If you’re planning on doing any video work at all on your laptop, make sure it has this port. Mercifully it’s pretty common, but I’ve seen a few laptops that don’t have it. Apple recently played a game of artifical market segmentation, also known as let’s see how difficult we can make things for the consumer, by removing the FireWire port from their less expensive and more portable refreshed MacBook line.

As for eSATA, I’m going to aggressively recommend you look for this in your next laptop and make it one of your must have features. Even if you don’t think you’ll use it, there’s always the possibility, and while you can get an ExpressCard that’ll add eSATA ports it will never feel as good as just being able to plug the drive into your laptop.

As for the ExpressCard and card reader … those come standard these days with most notebooks. You’d be hard pressed to find a new machine with a PC Card slot and frankly you’re better off for it, as ExpressCard is the superior standard and more and more peripherals are coming out which support it.

Finally, in terms of video output, HDMI is becoming much more common these days. If you’re planning to use an external monitor with your new laptop, I’d strongly recommend seeking out a laptop with either HDMI or DVI. If you’re going to use your laptop as a potential portable media center, HDMI is a slam dunk, as it will allow you to connect sound and digital video in a single cable.

Try to remember that an HDMI port is just as good as a DVI port for a second monitor, it just might need an adaptor. Your laptop also have multiple monitor outputs – say a DVI and a VGA. Do not be fooled, you can not use them both simultaneously. Modern graphics hardware only supports two graphics outputs at the same time, and one of those is going to be the laptop screen.





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