Computers
as a Second LanguageComputers
as a Second LanguageWhat Makes a Good Computer
VIDEO
DISPLAY CARD If
there's one area where a potentially fast computer can be slowed to a
crawl, it's the video display. Two computers equipped with identical
PENTIUM CPUs, identical SD-RAM, identical RAM caches, identical hard
drives, can look like the tortoise and the hare
when only one of them is equipped with a high speed video display card.Video
display cards contain their own RAM chips. Today's bare minimum standard
is 1 MB of RAM on the video card. These RAM chips hold
the image that the monitor is actively displaying. Since the image on
the monitor changes very frequently, it is important to have great
performance from your video card. There are two main factors that affect
the performance of a video card.First,
what kind of RAM chips are on the card? The inexpensive computer uses
DRAM (Dynamic RAM)
chips which are slower than the VRAM (Video
RAM) or WRAM (Windows
RAM) that's used on better video cards.Second,
does the video card include its own accelerated microprocessor
circuitry? Good accelerators are capable of re-drawing the screen as
fast as the fastest CPU dishes out the data.In
our example, the bargain computer is equipped
with a cheap $50.00 video board with 1 MB of DRAM
and a minimal accelerator. The CPU has to keep waiting for the video
card to "catch up" as the data is delivered. Performance
really suffers. By contrast, the $200.00 video board in the other
computer contains 4 MB of faster WRAM
and a 64-bit accelerator that can take data from the PENTIUM CPU as fast
as it's dished out!Here's
another important point. The cheap video card has only 1 MB of DRAM with
no possibility of increasing the DRAM in the future. The $200.00 card
has another empty socket on it to add another
4 MB of WRAM in the future if desired. Why would you want so much WRAM
on the display card? This issue merits more investigation and will be
discussed in the next section. |
