Chapter 11: Expansion Cards^237
You can find sound cards for both the ISA and PCI interfaces, but most sources rec-
ommend using the PCI interface. ISA cards are the least expensive and sound like it. If
you want to watch DVD movies (assuming you have a DVD drive), play games, or listen
to your Napster downloads on your PC, a PCI card is your best bet.
As with most expansion cards, about the only problem you’ll run into when installing
a sound card in a PC is system resource conflicts, especially IRQs. See the “Trouble-
shooting Expansion Cards” section of this chapter for more information on resolving
resource conflicts for expansion cards. Chapter 21 goes into detail on the various features
and components found on sound cards and just what they are and do.
Sound Card Voices
One rule of thumb you can use to judge how good the sound produced by a sound card
will be is the number of voices it reproduces. A voice on a sound card is essentially one
instrument. For example, a piano sound is one voice, a trumpet another, a drum, a third,
and so on. The number in the sound card’s model name, such as SoundBlaster 16, Sound-
wave 32, or a SoundBlaster AWE64, is the number of voices it can reproduce. Contrary to
common belief, this number is not how many bits the sound card uses to decode sound
samples. The resolution of the sound in bits describes the sound’s amplitude and frequency.
Nearly all PC sound cards use a 16-bit digital sound resolution, the same used on CD
players and CD-ROM drives.
Speakers
Don’t forget that the sound card is only half the puzzle; in order to hear the sound, the PC
must have a set of speakers. Most sound cards have a full set of output jacks into which
you can plug your speakers and connect to amplifiers and microphones. Just as with the
sound card, you get what you pay for with speakers. Luckily, nearly all PCs now come
withasoundcardandasetofspeakersasstandardequipment.But,ifyouwanttoupgrade
the sound, verify the capabilities of the sound card first. It could be that the speakers are
just not robust enough to handle what may be a quality sound card. If the speakers are
good quality, then upgrade the sound card.
Video Cards
Depending on how you look at it, your PC’s video card may be the most important ex-
pansion card in your system. The video card provides your PC with its ability to display
images, text, and graphics on the monitor. Some newer motherboards now integrate the
video processing into the chipset or on the motherboard itself, but for the vast number of
PCs in use, a video expansion card is used to drive the video signal.
To provide the best possible image, the video card must be matched to the monitor it
drives (see Chapters 12 and 16 for information on video cards and monitors). These two
components must be matched in their capabilities. The video card must be able to drive
the monitor, and the monitor must be able to display the output of the video card.
When choosing a video card for a PC, you should look at three important features or
components: its processor or chipset, its bus, and its memory.