CompTIA A_ Certification All-In-One Exam Guide, Seventh Edition - Michael Meyers [474]
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NOTE Second Life is a massively multiplayer online role-playing game (MMORPG) that offers a unique twist on the genre. You can create just about anything you can imagine, as far as your time and talent can take you. Second Life has a functioning economy that spills out into the real world, meaning you can buy and sell things within the game and turn that into real U.S. dollars, although the more common scenario is to spend real money to get virtual possessions.
The keyboard controller reads the grid of your keyboard and, on discovering your input, sends the information to the CPU through the wires of the motherboard (Figure 27-3). The CPU understands the keyboard controller because of a small program that was loaded into RAM from the ROM BIOS on the motherboard when the PC booted up.
Figure 27-3 Keyboard to CPU
The CPU and the application determine what should happen in the game, and on discovering that your character is about to cross the zone line, they trigger a whole series of actions. The application sends the signal to the OS that it needs a specific area loaded into RAM. The OS sends a signal to the CPU that it needs data stored on the hard drive plus information stored on the Second Life servers. The CPU then sends the commands to the hard drive controller for it to grab the proper stored data and send it to RAM, while at the same time sending a command to the NIC to download the updated information (Figure 27-4).
Figure 27-4 CPU to hard drive and NIC
The hard drive controller tells the hard drive to cough up the data—megabytes worth—and then sends that data through the motherboard to the memory controller, which puts it into RAM and communicates with the CPU when it’s finished. The network card and network operating system communicate with the Second Life servers and download the necessary updated information. The CPU then uses the application and OS to process the new data, sending video data to the video card and sound data to the sound card, again through the wires on the motherboard (Figure 27-5).
The video card processor puts the incoming data into its RAM, processes the data, and then sends out commands to the monitor to update the screen. The sound card processor likewise processes the data and sends out commands to the speakers to play a new sound (Figure 27-6).
Figure 27-5 CPU to video card and sound card
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NOTE Windows Vista has raised the bar on video demands in a big way, so the video card in your users’ systems can make a remarkable difference in their experience. Vista uses the video card to produce many of the cool visual effects of the interface. This means that a low-end video card in an otherwise serviceable machine can cause Vista to misbehave. Unless your client is gaming, there’s no reason to drop $300+ on a video card, but assembling or recommending a system with yesterday’s video is not necessarily a good thing!
For all of this to work, the PC has to have electricity, so the direct current (DC) provided by the power supply and the alternating current (AC) provided to the power supply must both be the proper voltage and amperage.
Finally, because Second Life is a network application, the OS has to send information through the NIC and onto the Internet to update everyone else’s computer. That way, the other characters in the game world see you move forward a step (Figure 27-7).
What do you see or hear with all these electrons zipping all over the place? Out of a seemingly blank vista (Figure 27-8), a castle begins to appear, building itself piece by piece as your computer processes the new information and updates the video screen. You hear music begin to play from your speakers. Within a few seconds, with the data describing the new island fully downloaded and processed,