Peripherals and Custom Computing
Date: Feb 2, 2016
The computer is built, the OS is installed, and video is configured. Now let’s discuss the devices and peripherals we add on to the computer, the ports they connect to, as well as some custom PC configurations you will undoubtedly encounter in the field.
Input/Output, Input Devices, and Peripherals
To take advantage of a computer, the appropriate input/output devices and peripherals must be connected to the proper input/output (I/O) ports. Keyboards, mice, and multimedia devices can be connected to a variety of ports. This section briefly describes those devices and the ports they connect to.
I/O Ports
I/O ports enable a user to input information by way of keyboard, mouse, or microphone; plus they enable the output of information to printers, monitors, USB devices, and so on. The CompTIA A+ exams require you to describe USB, IEEE 1394 (FireWire), and Thunderbolt ports, as well as Bluetooth technology. The most common of these by far is USB.
USB
USB ports are used by many devices, including keyboards, mice, printers, flash drives, cameras, and much more. The USB port enables data transfer between the device and the computer and usually powers the device as well. The speed of a USB device’s data transfer depends on the version of the USB port, as shown in Table 13.1.
TABLE 13.1 Comparison of USB Versions
USB Version |
Name |
Data Transfer Rate |
USB 1.0 |
Low-Speed |
1.5 Mb/s |
USB 1.1 |
Full-Speed |
12 Mb/s |
USB 2.0 |
High-Speed |
480 Mb/s |
USB 3.0 |
SuperSpeed |
5.0 Gb/s |
USB 3.1 |
SuperSpeed+ |
10.0 Gb/s |
USB 1.0 and 1.1 are deprecated. If you encounter an older computer that has only these ports, consider installing a USB adapter card that adheres to a higher version of USB.
A computer can have a maximum of 127 USB devices. However, most computers are limited to a maximum of a dozen ports or so. To add devices beyond this, a USB hub can be used, but no more than five hubs can be in a series of USB devices. All cables connecting USB devices must comply with their standard’s maximum length. USB version 1.1 cables are limited to 3 meters in length (a little less than 10 feet), and USB version 2.0 cables can be a maximum length of 5 meters (a little more than 16 feet). Maximum recommended USB 3.0/3.1 length is 3 meters. The standard USB cable has four pins: a +5 V pin for power, a positive data pin, a negative data pin, and a ground pin. Most USB connections are half-duplex, meaning that the device can send or receive data but cannot send and receive data simultaneously.
There are various plugs used for the different types of USB connections. The most common are Type A and Type B, which are 4-pin connectors, but there are also mini- and micro-connectors, which are 5-pin. Type A connectors are the type you see on the back of a computer or on the side of a laptop. Figure 13.1 displays an illustration of these connectors.
FIGURE 13.1 USB connectors
Type A and Type B connectors are commonly used for printers and other larger devices. Mini- and micro-connectors are often used for handheld computers, smartphones, mice, digital cameras, portable music players, and cell phones. However, some companies create proprietary cables and connectors for their devices based off of the USB specifications. These devices will not connect properly to Type A, Type B, and mini- or micro-connectors.
You can’t put a square peg in a round hole (normally). Sometimes you need to make a connection but the devices and/or cables don’t match up, so you’ll need an adapter—and there are adapters for virtually everything you might want to do. Let’s say you need to make a connection to a USB Type B connector from a USB Type A connector, or you need to connect from USB to RJ45, or you need to connect from a USB to the older PS/2 connector—well, there are adapters for all of those situations and more. Most PC technicians will carry a variety of adapters with them just in case the need arises. Something to think about for your PC toolkit.
Historically, a USB device was designed to be a host or a slave. The host is in charge of initiating data transfers (for example, a PC). However, USB version 2.0 introduced on-the-go (OTG), which enables a device to act as both a host and a slave. This is more common in handheld computers and smartphones (devices that connect with either mini- or micro-plugs).
USB devices connect to what is known as a root hub, regardless of whether they are USB version 1.1, 2.0, or 3.0 devices. The USB devices, root hub, and host controllers can be viewed from within Windows in a couple ways:
- Device Manager: Within Device Manager, click Universal Serial Bus Controllers to expand it. The root hub and controllers are listed within. Individual devices will be listed under such categories as Human Interface Devices.
- System Information: Open System Information by opening the Run prompt and typing msinfo32. Expand Components, and then select USB.
Windows offers a disk-caching component called ReadyBoost. This uses flash-based memory such as USB flash drives and SD cards to cache information for the OS at high speeds. The cache can be as much as 32 GB in size on one device or 256 GB in size if spread across multiple devices. For USB flash drives, this technology works best at USB 3.0 speeds (or higher).
When troubleshooting USB devices, keep a few things in mind:
- Verify that USB is enabled in the BIOS/UEFI: It is possible to enable/disable USB within the BIOS. Keep this in mind when troubleshooting USB devices that are not functioning whatsoever. The user might have inadvertently set this to disabled or perhaps the computer was shipped in that state.
- Make sure the computer is running the correct version of USB: For example, if the computer is USB 3.0-compliant from a hardware standpoint, make sure it is running USB 3.0 on the software side. Some versions of Windows need to be updated to communicate at the latest USB speeds. This update makes a huge difference in the speed of data transfer. Sometimes Windows informs the user that an update to USB is available and that the USB devices work faster if this update is completed. In other cases, a USB firmware update for the motherboard is needed.
- Check the version of the USB port: For example, if a device can run at USB 3.0, make sure it isn’t connected to a USB 2.0 (black port), because that will cause the device to run at USB 2.0 speeds. If it is connected to a slower port, be sure to connect it to a USB 3.0 (blue) port.
- Verify connectivity: Make sure the device is plugged in and that it is using the correct cable. Some incompatible USB plugs might look similar to the correct plug and might even connect to a device.
When removing USB devices from a computer, remember to disable them in the Notification Area before disconnecting them. Do this by right-clicking on the Safely Remove Hardware and Eject Media icon and selecting Eject. This will avoid damage to a USB device (for example, corruption to the USB flash drive). If you cannot disable it in the system, power down the computer and then disconnect them. For more information about USB, visit http://www.usb.org.
One of the problems with USB is that it suffers from latency. Due to this fact, users who work with audio and video prefer a zero-latency connection, such as IEEE 1394.
IEEE 1394
The Institute of Electrical and Electronics Engineers (IEEE) is a nonprofit organization that creates standards regarding cables and connectors and other technology related to electricity. One common standard is IEEE 1394, also referred to as FireWire (a deprecated Apple standard replaced by Thunderbolt). It is a port used for devices that demand the low-latency transfer of data in real time, such as music or video devices. Up to 63 devices can be powered by a computer, with no more than 16 devices per chain. Table 13.2 describes some of the IEEE 1394/FireWire versions.
TABLE 13.2 Comparison of IEEE 1394/FireWire Versions
IEEE 1394 Version |
Data Transfer Rate |
Connector Type |
Cable Length Between Devices |
IEEE 1394a |
400 Mb/s |
4-conductor and 6-conductor |
4.5 meters (15 feet) |
IEEE 1394b |
800 Mb/s |
9-conductor |
10 meters (100 meters with Category 5e cable) |
Thunderbolt
Thunderbolt is a high-speed hardware interface developed by Intel. As of the writing of this book, this is used primarily by Apple computers. It combines elements of PCI Express and DisplayPort technologies. Versions 1 and 2 use the Mini DisplayPort connector and version 3 uses the USB Type-C connector. Cables used with Thunderbolt should be no more than 3 meters (copper) and 60 meters (optical).
Thunderbolt 2 gives you access to the latest 4K monitors. In fact, with the Mac Pro, you can connect up to three 4K displays at once. And because Thunderbolt is based on DisplayPort technology, it provides native support for the Apple Thunderbolt Display and Mini DisplayPort displays. DVI, HDMI, and VGA displays connect through the use of adapters.
Thunderbolt can be used to transfer data at high rates to external storage devices or to displays (or both; up to six devices can be daisychained, meaning wired together in sequence). If you look at the ports of the computer and see the thunderbolt icon next to the Mini DisplayPort port, then it is meant to be used for data transfer to peripherals. If you see a display icon, then it can be used with a monitor. While you can physically connect a Thunderbolt device to a Mac with DisplayPort, the device will not work, but if you connect a DisplayPort device to a Mac with Thunderbolt, the device will work. Table 13.3 describes the different versions of Thunderbolt.
TABLE 13.3 Comparison of Thunderbolt Versions
Thunderbolt Version |
Data Transfer Rate |
Connector Type |
PCI Express Version Required |
Version 1 |
10 Gb/s |
DisplayPort |
Version 2.0 |
Version 2 |
20 Gb/s |
DisplayPort |
Version 2.0 |
Version 3 |
40 Gb/s |
USB Type-C |
Version 3.0 |
If a desktop computer doesn’t come with a Thunderbolt connector, you can add a Thunderbolt adapter card, which can facilitate the use of high-speed, large-capacity storage devices and other technologies. There are also adapters that connect Thunderbolt to USB 3.0 and eSATA. On the video side, there are adapters that allow Thunderbolt to be changed over to DVI or to HDMI. As mentioned before, there are adapters for everything. If you can dream it up, it probably already exists.
PS/2
The PS/2 connector is used for connecting keyboards and mice to a desktop computer or laptop. The PS/2 port was originally introduced in the late 1980s as part of IBM’s Personal System/2 computer. Keyboards and mice connect via a 6-pin Mini-DIN connector. In the PC 99 color scheme, PS/2 keyboard ports are purple and PS/2 mouse ports are green.
Although PS/2 had almost a 20-year run, these connectors are less common on new computers; they were the standard until USB became popular. However, like the older DB15 VGA port, you might see them for backward compatibility. For example, the AV Editor computer’s motherboard has a single PS/2 port.
Bluetooth
Moving on to a wireless option for peripherals: Bluetooth is a short-range, low-speed wireless network primarily designed to operate in peer-to-peer mode (known as ad hoc) between PCs and devices such as printers, projectors, smartphones, mice, keyboards, and so on. It can be used with gaming consoles and by connecting a smartphone to a car’s technology system or to a smart TV.
Bluetooth runs in virtually the same 2.4 GHz frequency used by IEEE 802.11b, g, and n wireless networks, but it uses a spread-spectrum frequency-hopping signaling method to help minimize interference. Bluetooth devices connect to each other to form a personal area network (PAN).
Some systems and devices include integrated Bluetooth adapters, and others need a Bluetooth module connected to the USB port to enable Bluetooth networking. Bluetooth devices must first be paired before they can be used together.
Bluetooth version 1.2 offers a data transfer rate of 1 Mb/s. Version 2 is rated at 3 Mb/s. Version 3 has theoretical speeds of up to 24 Mb/s, but it does so by combining with 802.11 technology. Bluetooth is divided into classes, each of which has a different range. Table 13.4 shows these classes, their ranges, and the amount of power their corresponding antennae use to generate signal.
TABLE 13.4 Bluetooth Classes
Class |
mW |
Range |
Class 1 |
100 mW |
100 meters (328 ft.) |
Class 2 |
2.5 mW |
10 meters (33 ft.) |
Class 3 |
1 mW |
1 meter (3 ft.) |
As you can see, Class 1 generates the most powerful signal and has the largest range. The most common Bluetooth devices are Class 2 devices, with a range of 10 meters. Examples of this include portable printers, headsets, and computer dongles that connect to USB ports and allow the PC to communicate with other Bluetooth-enabled devices.
Input, Output, and Hybrid Devices
I/O devices (also called peripherals) can be used solely to input information, to output information, or to act as a hybrid of the two. Let’s start with the types of devices used to input information and the various peripherals a technician might see in the field.
The usual suspects include the keyboard, for typing information in Windows or other OS, and the mouse, for manipulating the GUI. These two are known as human interface devices (HID). Some other devices that you might not have worked with yet include touchpads, digital cameras, web cameras, microphones, biometric devices, bar code readers, and MIDI devices. Table 13.5 describes these devices.
TABLE 13.5 Description of Various Input Devices and Peripherals
Device |
Description |
Types and Connections |
Keyboard |
Used to type text and numbers into a word processor or other application. |
101-key keyboard is standard, USB, PS/2, and wireless connections. |
Mouse |
Used to control the GUI; works in two dimensions. Might have two or more buttons and a scroll wheel to manipulate the OS. The Buttons tab in Mouse Properties is used to change which buttons act as the primary and alternative click buttons. |
Optical mouse, USB, PS/2, and wireless connections. |
Touchpad |
Device used on a laptop to control the cursor on the screen. |
These are often integrated to the laptop but can also be connected externally via USB or Wi-Fi. |
Motion sensor |
Device used with PCs, Macs, and gaming consoles to allow a user to control the computer by swiping, grabbing, pinching, and so on in mid-air. |
Often connected via USB or Wi-Fi, these are controlled with infrared technology. Some devices can also be controlled with voice activation. |
Digital cameras/Camcorders |
Takes still photographs and/or video using an electronic image sensor. Images are displayed on-screen and can be saved to solid-state media such as SD cards and CompactFlash. |
Can be a single device or integrated into smartphones/tablets. Can connect to the PC via USB or Wi-Fi. |
Web cameras (webcam) |
Enables a user to monitor other areas of a home or building, communicate via video telephony, and take still images. |
Can connect to a PC via USB, to a LAN via RJ45, or via Wi-Fi. |
Scanner |
Used to optically scan images and other objects and convert them into digital images to be stored on the computer. |
Can connect via USB, and IEEE 1394, or via Wi-Fi. |
Microphones |
Enables users to record their voices or other sounds to the computer. Common usages are webcasts, podcasts, for voice-overs while screen capturing, and for gaming. |
Can connect to a PC via 1/8-inch (3.5 mm) mini-jack (sound card) or via USB. |
Biometric devices |
Provides access to systems based on a particular physical characteristic of a user. Used for authentication purposes (for example, a fingerprint reader). |
Can be integrated to the PC or can be connected via USB, Wi-Fi, or connected to the network. |
Barcode readers |
Reads barcodes (for example, linear barcodes, 2D barcodes, Post Office barcodes, and such). After physical installation, they need to be programmed to understand these codes. |
Connects to the PC via USB, Wi-Fi, PS/2, or might be integrated into handheld computers and smartphones. |
Smart card reader |
Device that accepts smart cards used for authentication and data storage. |
Can be integrated as a slot (for, example to a laptop). Also available in USB versions. |
Musical Instrument Digital Interface (MIDI) devices |
Enables computers, music keyboards, synthesizers, digital recorders, samplers, and so on to control each other and exchange data. |
Uses a 5-pin DIN Connector. |
Gamepads and joysticks |
Gamepads are game controllers made famous by Nintendo, PlayStation, and Xbox; there are also gamepads for PCs. Joysticks are often used for flight simulator games. |
Connects via USB Type A connections. Older versions used the 15-pin gaming port on a sound card. |
Troubleshooting any of the devices in Table 13.5 is usually quite easy. Make sure that the device is connected properly to the computer (or has a working wireless connection) and verify within the Device Manager that the latest drivers are installed for the device. Then find out if any additional software is necessary for the device to function. Portions of the software might have to be installed to the device and to the OS.
Keyboards and mice can be especially troublesome. Keyboard errors are commonly caused by jammed keys and defective cables or cable connectors. A common mouse issue is when the cursor jumps around the screen. This could be due to an incorrect mouse driver or perhaps the mouse is on an uneven or nonreflective surface. Also, you might encounter a mouse that stops working after a computer comes out of sleep mode. Make sure that Windows is updated and that the correct and latest driver is being used for the mouse. Use the associated Control Panel apps to troubleshoot the device. Calibrate the device and/or synchronize the device to the system as necessary.
The main output devices you should know for the exams are display devices and speakers (covered in Chapter 12) and printers (to be discussed in Chapter 14). Because they are covered in those chapters, we will not discuss them here.
A few of the hybrid devices you will encounter are touchscreens, KVMs, smart TVs, and set-top boxes. Table 13.6 describes those in brief.
TABLE 13.6 Description of Hybrid I/O Devices
Device |
Description |
Types and Connections |
Touchscreen |
A video display that detects the presence of either a finger, stylus, or light pen that enables interaction with the OS. It incorporates a digitizer (the input portion of the device) that converts the tapping on the screen into digital functions. |
Used in tablet PCs, AIO PCs, smartphones, and drawing tablets. |
KVM switch |
Enables a user to control two or more computers from one Keyboard, Video display, and Mouse (KVM). |
Passive: works off computer’s USB power Active: plugs into an AC outlet. |
Smart TV |
Combines the functionality of a television with Internet features and streaming of media. |
Users can interact with the TV by inputting information via keyboard, gamepad, or remote control. |
Set-top box (STB) |
Device used by cable TV and satellite-based TV providers to allow access to digital (and possibly encrypted) television stations. Also used as a hybrid device that combines conventional TV with Internet technologies. |
These often manifest themselves as small computers offering two-way communications over TCP/IP networks. |
Cram Quiz
Answer these questions. The answers follow the last question. If you cannot answer these questions correctly, consider reading this section again until you can.
220-901 Questions
What is the data transfer rate (speed) of USB 3.0?
- A. 12 Mb/s
- B. 400 Mb/s
- C. 480 Mb/s
- D. 5 Gb/s
What is the maximum number of USB devices a computer can support?
- A. 4
- B. 63
- C. 127
- D. 255
Which type of USB connector is normally found on a desktop PC or laptop?
- A. Type A
- B. Type B
- C. Type C
- D. Type D
What is the maximum data transfer rate of IEEE 1394a?
- A. 400 Mb/s
- B. 800 Mb/s
- C. 5 Gb/s
- D. 24 Mb/s
You just installed a barcode reader to a laptop. What should you do next?
- A. Adjust the light wavelength.
- B. Test the reader by reading barcodes.
- C. Program the reader to recognize codes.
- D. Point the barcode reader at someone.
What does a KVM do?
- A. Connects a computer to Bluetooth-enabled devices
- B. Allows multiple users to share a single computer
- C. Networks multiple computers together
- D. Connects multiple computers to save resources
You are installing a wireless keyboard to a PC. What does the PC require?
- A. Bluetooth dongle
- B. Thunderbolt connection
- C. Ethernet connection
- D. IEEE 1394
A user calls you with a complaint that none of his USB devices are working. What is the most probable cause?
- A. The USB 3.0 controller has failed.
- B. The root hub is not configured.
- C. The USB is disabled in the BIOS.
- D. The USB is disabled in Windows.
You plug a USB device into the front panel port of a PC but nothing happens. What is the most likely cause?
- A. The front panel connectors are not plugged into the motherboard.
- B. You plugged a USB 3.0 device into a USB 2.0 port.
- C. You need to reboot the computer.
- D. You plugged a USB 2.0 device into a USB 3.0 port.
Which of the following has a data transfer rate of 40 Gb/s and uses a USB Type-C connector?
- A. USB 3.1
- B. Thunderbolt version 3
- C. Bluetooth version 3
- D. Thunderbolt version 2
Which of the following are considered both input and output devices?
- A. Keyboard, mouse, touchpad
- B. Smart card reader, motion sensor, biometric device
- C. Printer, speakers
- D. Smart TV, touchscreen, KVM, STB
Cram Quiz Answers
220-901 Answers
- D. 5 Gb/s is the data rate for USB 3.0; 12 Mb/s is the data rate for USB version 1.1; and 400 Mb/s is the data rate of IEEE 1394a (FireWire 400). USB 2.0 has a maximum data transfer rate of 480 Mb/s.
- C. USB can support up to 127 devices on one computer. However, USB hubs will be necessary to go beyond the number of USB ports (usually 4 or 6) commonly found on a system. FireWire supports up to 63 devices.
- A. Type A connectors are almost always included on desktop PCs and laptops.
- A. IEEE 1394a (FireWire 400) specifies a maximum data transfer rate of 400 Mb/s. IEEE 1394b (FireWire 800) specifies 800 Mb/s. USB 3.0 runs at 5 Gb/s. Bluetooth version 3 runs at 24 Mb/s.
- C. After installing the device as well as the driver for the device, program the reader to recognize the codes.
- D. A KVM connects multiple computers to a single keyboard, mouse, and monitor. This way, fewer resources in the way of peripherals (input/output devices) are necessary to use the computers.
- A. Wireless keyboards and mice often use Bluetooth to transmit to a PC or laptop. The computer must either have a built-in Bluetooth antenna or a Bluetooth dongle connected to a USB port for the keyboard to function. These types of devices do not connect to Thunderbolt, Ethernet, or IEEE 1394 ports.
- C. If none of the USB devices are working, chances are that USB has been disabled in the BIOS. This might be company policy so that users can’t access USB drives or boot the computer to a USB drive. If the USB 3.0 controller fails, the USB 2.0 controller should still be functioning for other ports. The USB root hub requires no configuring; it is auto-configured by Windows. Although it might be possible to disable one USB device at a time in Windows, it will be uncommon. Disabling all the devices in Windows is rare.
- A. Most likely, the front panel connectors are not plugged into the motherboard. A USB 3.0 device will work fine in a USB 2.0 port but at the lower speed. A USB 2.0 device will work at USB 2.0 speed when plugged into a USB 3.0 port. Rebooting is usually not necessary when installing USB devices.
- B. Thunderbolt version 3 has a data transfer rate of 40 Gb/s and uses a USB Type-C connector. Although SuperSpeed+ USB 3.1 can use the newer USB Type-C connector, it has a data transfer rate of 10 Gb/s. Bluetooth version 3 has theoretical speeds up to 24 Mb/s. Thunderbolt version 2 transfers data at 20 Gb/s and uses a DisplayPort (or Mini DisplayPort) connector.
- D. Smart TVs, touchscreens, KVMs, and STBs are considered both input and output devices. Keyboards, mice, touchpads, smart card readers, motion sensors, and biometric devices are considered input devices. Printers and speakers are considered output devices.
Custom PC Configurations
There are several custom configurations that you might encounter in the IT field. You should be able to describe what each type of computer is and the hardware that is required for these custom computers to function properly.
Audio/Video Editing Workstation
Multimedia editing, processing, and rendering require a fast computer with high-capacity storage and big displays (usually more than one). Examples of audio/video workstations include
- Video recording/editing PCs: These run software such as Adobe Premiere Pro, Final Cut, or Sony Vegas.
- Music recording PCs: These run software such as Logic Pro or Pro Tools.
This just scratches the surface, but you get the idea. These computers need to be designed to easily manipulate video files and music files. So from a hardware standpoint, they need a specialized video or audio card, the fastest hard drive available with a lot of storage space (definitely SSD and perhaps SATA Express or PCI Express-based), and multiple monitors (to view all of the editing windows). Keep in mind that the video cards and specialized storage drives are going to be expensive devices; be sure to employ all antistatic measures before working with those cards.
CAD/CAM Workstation
Computer-aided design (CAD) and computer-aided manufacturing (CAM) workstations are common in electrical engineering, architecture, drafting, and many other engineering arenas. They run software such as AutoCAD. This software is CPU-intensive and images require a lot of space on the screen. Hardware-wise, a CAD/CAM workstation needs a powerful, multicore CPU (or more than one if you are using advanced CAD software or if you are performing 3-D design/rendering), a high-end video card (perhaps a workstation-class video card—much more expensive), and as much RAM as possible. If a program has a minimum RAM requirement of 2 GB of RAM, you should consider quadrupling that amount; plus, the faster the RAM, the better—just make sure your motherboard (and CPU) can support it.
Virtualization Workstation
A virtualization workstation is a computer that runs one or more virtual operating systems (also known as virtual machines or VMs). Did you ever wish that you had another two or three extra computers lying around so that you could test multiple versions of Windows, Linux, and possibly a Windows Server OS all at the same time? Well, with virtual software, you can do this by creating virtual machines for each OS. But if you run those at the same time on your main computer, you are probably going to bring that PC to a standstill. However, if you build a workstation specializing in virtualization, you can run whatever operating systems on it that you need. The virtualization workstation uses what is known as a hypervisor, which allows multiple virtual operating systems (guests) to run at the same time on a single computer. It is also known as a virtual machine manager (VMM). But there are two different kinds:
- Type 1: Native: This means that the hypervisor runs directly on the host computer’s hardware. Because of this, it is also known as bare metal. Examples of this include VMware vSphere and Microsoft Hyper-V.
Type 2: Hosted: This means that the hypervisor runs within (or “on top of”) the operating system. Guest operating systems run within the hypervisor. Compared to Type 1, guests are one level removed from the hardware and therefore run less efficiently. Examples of this include Microsoft Virtual PC and Oracle VirtualBox. Figure 13.2 shows an example of VirtualBox. You will note that it has a variety of virtual machines inside, such as Windows 7, Windows Server, and Linux Ubuntu.
FIGURE 13.2 VirtualBox Manager window
Generally, Type 1 is a much faster and efficient solution than Type 2. Because of this, Type 1 hypervisors are the kind used for virtual servers by web-hosting companies and by companies that offer cloud-computing solutions. It makes sense, too. If you have ever run a powerful operating system such as Windows Server within a Type 2 hypervisor such as Virtual PC, you know that a ton of resources are used and those resources are taken from the hosting operating system. It is not nearly as efficient as running the hosted OS within a Type 1 environment. However, keep in mind that the hardware/software requirements for a Type 1 hypervisor are more stringent and more costly. In addition, you need to make sure your CPU supports virtualization. For example, some CPUs do not support Intel Virtualization Technology (VT). To check whether your CPU can support VT, http://ark.intel.com/Products/VirtualizationTechnology.
Intel CPUs that support x86 virtualization use the VT-x virtualization extension. Intel chipsets use the VT-d and VT-c extensions for input-output memory management and network virtualization, respectively. AMD CPUs that support x86 virtualization use the AMD-V extension. AMD chipsets use the AMD-Vi extension.
Any computer designed to run a hypervisor often has a powerful CPU (or multiple CPUs) with four cores or more and as much RAM as can fit in the system. This means a powerful, compatible motherboard as well. So in essence, the guts—the core of the system—need to be robust. Keep in mind that the motherboard BIOS/UEFI and the CPU should have virtualization support.
In general, the security of a virtual machine operating system is the equivalent to that of a physical machine OS. The VM should have the latest updates, the newest AV definitions, perhaps a personal firewall, strong passwords, and so on. However, there are several things to watch out for that, if not addressed, could cause all your work compartmentalizing operating systems to go down the drain. This includes considerations for the virtual machine OS as well as the controlling virtual machine software. Keep an eye out for network shares and other connections between the virtual machine and the physical machine or connections between two VMs.
Consider disabling any unnecessary hardware from within the virtual machine, such as optical drives, USB ports, and so on. One last comment: A VM should be as secure as possible, but, in general, because the hosting computer is in a controlling position, it is likely more easily exploited. A compromise to the hosting computer probably means a compromise to any guest operating systems. Therefore, if possible, the host should be even more secure than the VMs it controls.
Thin Client
A thin client (also known as a slim, lean, or cloud client) is a computer that has few resources compared to a typical PC. Usually, it depends heavily on a server. It is often a small device integrated directly into the display or could be a stand-alone device using an ultra-small form factor (about the size of a cable modem or gaming console). Some thin clients are also known as diskless workstations because they have no hard drive or optical discs. They do have a CPU, RAM, and ports for the display, keyboard, mouse, and network; they can connect wirelessly as well. They are also known simply as computer terminals which might provide only a basic GUI and possibly a web browser. There is a bit of a gray area when it comes to thin clients due to the different models and types over the years, but the following gives a somewhat mainstream scenario.
Other examples of thin clients include point-of-sale (POS) systems such as the self-checkout systems used at stores or touchscreen menus used at restaurants. They serve a single purpose and require minimum hardware resources and minimum OS requirements.
When a typical thin client is turned on, it loads the OS and applications from an image stored (embedded) on flash memory or from a server. The OS and apps are loaded into RAM; when the thin client is turned off, all memory is cleared.
So, the thin client is dependent on the server for a lot of resources. Thin clients can connect to an in-house server that runs specially configured software or they can connect to a cloud infrastructure to obtain their applications (and possibly their entire operating system).
The whole idea behind thin clients is to transfer a lot of the responsibilities and resources to the server. With thin-client computing, an organization purchases more powerful and expensive servers but possibly saves money overall by spending less on each thin client (for example, Lenovo thin clients) while benefitting from a secure design. The typical thin client might have one of several operating systems embedded into the flash memory, depending on the model purchased. This method of centralizing resources, data, and user profiles is considered to be a more organized and secure solution than the typical PC-based, client/server network, but it isn’t nearly as common.
Standard Thick Client
A standard thick client, or fat client, is effectively a PC. Unlike a thin client, a thick client performs the bulk of data processing operations by itself and uses a drive to store the OS, files, user profile, and so on. In comparison to thin clients and the somewhat centralized computing, with a thick client, a typical local area network of PCs would be known as distributed computing, where the processing load is dispersed more evenly among all the computers. There are still servers, of course, but the thick client has more power and capabilities compared to the thin client. Distributed computing is by far the more common method today. When using a thick client, it’s important to verify that the thick client meets the recommended requirements for the selected OS.
An example of a standard thick client is a desktop computer running Windows 8 and Microsoft Office, and offers web browsing and the ability to easily install software. This standard thick client should meet (or exceed) the recommended requirements for Window 8, including a 1 GHz 64-bit CPU, 2 GB of RAM, and 20 GB of free hard drive space.
Home Server PC
A real server runs software such as Windows Server or Red Hat Enterprise Linux. But this software is expensive and requires a lot of know-how. For the average home user, a server OS is not usually necessary. It requires too much money and hardware resources and takes too much time to configure. However, if you want to have a home server PC, you can do so with any Windows OS that can start a HomeGroup, a Mac with OS X, or with most desktop variants of Linux. Once that computer is configured properly, information can be stored centrally on that system. Files and printers can be shared to the rest of the devices on the network, and media can be streamed to the other systems as well. To configure media streaming in Windows, go to Control Panel > HomeGroup, and then click the Change advanced sharing settings link. Open the appropriate network type and then click the Choose media streaming options link. Turn on media streaming and then click Customize for any particular device. From these last two locations, you can choose what is to be streamed, and you can select parental ratings if you want.
To make this server function quickly and recover from faults, we would equip it with a gigabit network adapter minimum (wired, for best results) and set up a RAID array. The RAID array could be RAID 0 (striping), but to incorporate fault tolerance, we would want RAID 1 (mirroring, 2 drives) or RAID 5 (striping with parity, 3 drives or more). To do this on a Windows system, we might need a RAID controller either embedded on the motherboard or installed as a separate adapter card. Or an external RAID array could be connected to the computer or connected to the network directly (NAS box) and controlled by the computer. Then we would need to configure file sharing and possibly print sharing, discussed in Chapters 16 and 14, respectively.
Home Theater PC (HTPC)
A home theater PC (HTPC) can take the place of a Blu-ray player, DVD player, CD player, and various audio equipment. In some cases, it can also take the place of a set-top box (STB) as well. However, this depends on the area you live in. It has become more difficult (but not impossible) to use the HTPC for television reception due to cablecards and encryption techniques.
The requirements for an HTPC include a small form factor (micro-ATX or mini-ITX), a quiet desktop case with a silent video card, and an HDMI output for connectivity to big-screen televisions or projectors. To keep the rest of the computer quiet, a liquid-cooled CPU (instead of fan-based) and solid-state hard drive would complete the equation. Surround sound audio is desired as well, whether it comes from a sound card on the computer or from an external source. Finally, if you want to get TV reception, you would need a TV tuner and possibly an antenna.
Home entertainment enthusiasts often have computers hooked up to their home theaters. If this is the case, they might install TV tuner cards. These cards can accept the signal from a cable or satellite provider or an over-the-air (OTA) antenna and then send it back out to the TV or other devices in the home theater. Some TV tuners also act as capture cards, meaning that they can capture the signal and record TV programs. Many come with a remote control (and IR blaster) so that the computer can be controlled in the same manner as a TV.
The purpose of all this is to record shows onto the computer and basically use the computer as a digital video recorder (DVR), among other things. By using programs such as Windows Media Center (WMC) and Kodi, users can control their TV experience. However, according to Microsoft, Windows 8.1 is the last OS that will support WMC.
TV tuner cards are available with PCI Express, PCI, ExpressCard and Mini PCIe (for laptops), and USB interfaces. TV tuners often have RG-6 connectors for cable in and antenna. Make sure you connect to the right one!
An HTPC is often also used as a home server PC because most of the requirements are the same.
Gaming PC
Now we get to the core of it: Custom computing is taken to extremes when it comes to gaming. Gaming PCs require almost all the resources mentioned previously: a powerful, multicore CPU; lots of fast RAM; one or more SSDs (SATA Express or PCI Express); advanced cooling methods (liquid cooling if you want to be serious); a high-end video card and specialized GPU; an above average, high-definition sound card; a big monitor that supports high resolutions and refresh rates; plus a fast network adapter and strong Internet connection (and mad skills). This all creates a computer that is expensive and requires care and maintenance to keep it running in perfect form. For the person who is not satisfied with gaming consoles, this is the path to take.
Games are some of the most powerful applications available. If even just one of these elements is missing from a gaming system, it could easily ruin the experience. The video card is a huge component of this equation. Gamers are always looking to push the envelope for video performance by increasing the number of frames per second (frames/s or fps) that the video card sends to the monitor. One of the ways to improve the video subsystem is to employ multiple video cards. It’s possible to take video to the next level by incorporating Nvidia’s Scalable Link Interface, known simply as SLI (previously Scan Line Interleave) or AMD’s CrossFire. A computer that uses one of these technologies has two (or more) identical video cards that work together for greater performance and higher resolution. The compatible cards are bridged together to essentially work as one unit. It is important to have a compatible motherboard and ample cooling when attempting this type of configuration. Currently, this is done with two or more PCI Express video cards (x16/version 3) and is most commonly found in gaming rigs, but you might find it in other PCs as well (such as video editing or CAD/CAM workstations). Because some motherboards come with only one PCIe x16 slot for video, a gaming system needs a more advanced motherboard: one with at least two PCIe x16 slots to accomplish SLI.
Cram Quiz
Answer these questions. The answers follow the last question. If you cannot answer these questions correctly, consider reading this section again until you can.
220-901 Questions
Which of the following is the best type of custom computer for use with Pro Tools?
- A. CAD/CAM workstation
- B. Audio/Video Workstation
- C. Gaming PC
- D. HTPC
What do CAD/CAM workstations require most?
- A. Liquid cooling and RAM
- B. TV tuner and silent hard drive
- C. Surround sound card and specialized GPU
- D. Powerful CPU and RAM
Your organization needs to run Windows in a virtual environment. The OS is expected to require a huge amount of resources for a powerful application it will run. What should you install Windows to?
- A. Type 2 hypervisor
- B. Gaming PC
- C. Type 1 hypervisor
- D. Thin client
What are some of the elements of a home server PC? (Select the two best answers.)
- A. Liquid cooling
- B. Fast network adapter
- C. The best CPU
- D. RAID array
- E. Gamepad
You just set up an HTPC. However, the Windows Media Center live TV option is not working. All connections are plugged in and all the other portions of Windows Media Center work. What is the most likely cause of the problem?
- A. The coax cable is plugged into the antenna port.
- B. Media Center needs to be reinstalled.
- C. Windows libraries are malfunctioning.
- D. The computer overheated.
Cram Quiz Answers
220-901 Answers
- B. The audio/video workstation is the type of custom computer that would use Pro Tools, Logic Pro, and other music and video editing programs.
- D. A CAD/CAM workstation most requires a powerful CPU and RAM. Liquid cooling, a surround sound card, and a specialized GPU are required by gaming PCs. TV tuners and silent hard drives are needed by HTPCs.
- C. If the virtual operating system needs a lot of resources, the best bet is a “bare metal” type 1 hypervisor. Type 2 hypervisors run on top of an operating system and therefore are not as efficient with resources. Gaming PCs have lots of resources but are not meant to run virtual environments. Thin clients have the least amount of resources.
- B and D. Home server PCs require a fast network adapter for the quick transfer of files over the network and a RAID array to offer fast and reliable access to data.
- A. If everything is working except for the live TV option, then the coax cable is probably plugged into the antenna port instead of the cable in port of the TV tuner card. This is also a common mistake on set-top boxes.