GPU, PPU, GRAM and your system part 1
Picking the right graphics card for your system
is hard enough, configuring that card to run your games at top performance
can be even harder. In this article
I hope to explain some of the technologies used in the newest games, and
how to configure your system to play those games
Today’s newest games take advantage
of a part of the computer dedicated to processing graphics. In the PC’s early era, graphics processing
was taken care of by the computer’s central processing unit (CPU) and RAM;
but as games became more advanced and the graphics displayed by those games
became more detailed, a CPU no longer cut it alone. For
years there have been add-on cards that can take over some of that workload
from the CPU. Starting with Windows
XP many computers came with a dedicated graphics processing unit, or GPU. These
are devices installed in the computer that are dedicated to the processing
of the graphics associated with your game. This
leaves your CPU and system RAM available to run the logical portion of the
game (enemies, missions, artificial intelligence, data location on the hard
drive, etc). GPU Cards have their on VPU (video processing
unit) and RAM dedicated to translating the data output by the game into a
signal your computer’s monitor can understand.
Before we get into the card, let’s talk about your game. Frame rate (FPS – Frames per second) is a term
you should familiarize yourself with. The
frame rate is how many times per second that your computer is able to update
the picture that you’re looking at. As
computer power has gotten cheaper and rendering technologies get better,
game developers can add all sorts of detail to a game to give it a lifelike
look and feel. All of these tiny details
have to be processed, or “thought about” by your computer. Basically this means the higher the level of
detail in the game, the lower your frame rate will be. You want to play your game at a detail level
that makes the game enjoyable, yet keeps the frame rate manageable. Your goal should be a FPS of 15-25. This will give the game quality as television,
as most TV signals show 24 frames of video per second.
Most of today’s games require a certain
video chipset, usually ATI’s X series (X1300, X1400, etc) or NVidia’s GeForce
6/7 chipset (GeForce 6600, GeForce 7100, etc). Logically, the higher the
number, the better the card. Don’t
get confused, many companies produce video cards, but almost all of them
will have either an ATI or NVidia chipset. The
card manufacturer isn’t as important as the chipset manufacturer. While
you want to make sure you can get the best card you can afford, you need
to make sure it is compatible with your system, and
the game you wish to play. Most
systems made prior to 2006 come with an AGP slot to plug a video card into,
most new systems come with a PCI Express (PCIe) type slot. AGP
comes in the 2x, 4x and 8x variety. The higher the ‘x’ number, the faster the card
is able to transfer data from the CPU bus to its VPU and vice-versa. Check your PC’s manual to find your AGP slot
type. Most newer AGP
slots support 2x, 4x and 8x but check carefully before purchasing. PCIe is the newest standard, in some cases
transferring data between the VPU and CPU at 8GB/s, 4 times the speed of
AGP 8x. If your system supports both
PCIe and AGP, you would want to purchase a PCIe type video card. When picking out a video card you want to purchase
the card that is compatible with your system and has the largest amount of
video RAM and the fastest processor you can afford. The minimum specifications you should shoot
for are 256MB RAM and a 400 MHz VPU. RAM
comes in DDR/GDDR, GDDR2 and GDDR3 (only available on ATI chipsets). Generally GDDR2 and 3 is better than GDDR,
but 512MB of GDDR is better than 128MB or 256MB of GDDR2/3.
Before we get into configuring your
system to run your new game, we need to touch on Physics cards (PPU – physics
processing unit). Physics cards do
the same job as a Video Card, except they concentrate specifically on producing
realistic physics for your video games. They
do this by plotting and maintaining the positions of up to millions of simulated
objects. Instead of the wall you shot
with your BFG9000 breaking into tens or dozens of pieces (each piece needing
CPU/VPU time to keep track of), the wall can shatter into thousands or hundreds
of thousands of pieces, giving the game a more realistic look and feel. It
is also the difference of only certain objects being interactive, to the
entire environment being available for the player to interact with. When
you run out of ammo, pick up that wooden crate or piece of 2x4 to bash your
enemy. The in-game possibilities are
almost endless. The only card on the
market right now, either to purchase or for video game developers to write
into their games is the PhysX card produced by AGEIA (http://www.ageia.com). The PhysX PPU card
is an add-on card for your PC that fits in a standard PCI slot. AGEIA writes a physics engine that any video
game developer can use to produce realistic physics for your game. UbiSoft’s Tom
Clancy’s Ghost Recon: Advanced Warfighter is an example of a game to
utilize the PhysX Engine. You don’t
necessarily have to have a PhysX card to run the game, but if you do, you’ll
be able to experience it in the form intended by the game’s developers. Using a PPU card gives the game a more lifelike
feel, with the player able to interact with ANY object displayed in the game. Leaves
on the trees move individually depending on the breeze, walls can be blown
into smithereens, dust and smoke blow realistically in the wind and bullets
and weapons have realistic ballistics. PPUs
are optional now, but I imagine as the technology takes off most PCs will
start to come with them pre-installed just as video cards progressed in the
early 2000s. If you can afford the additional $300 for a
PPU card, it is well worth the money.
