GeForce
256 Roundup
Nov,
1999
Difficult
to get, too hot to handle.
If I had a company that sold video accelerators, I'd probably have sleepless
nights and pop antacids every hour or so over Nvidia's new GeForce 256. Nvidia
is in an enviable position from a technology as well financial point of view.
They are the first to deliver the next-generation
3D chip, several months ahead of the rest, at that. Although S3 is about to
ship the first Savage 2000s at the time of this writing, they still place
a distant second. Nvidia's fiercest competitor, 3dfx, is still working on
VSA-100, and it is not expected until the middle of the year. Hanging far
back from the leader are Matrox and ATI, both of them still stuck with RIVA
TNT2-generation accelerators. Permedia, Intel, 3DLabs and the others seemed
to have retired from the race.
Needless to say, the suits at Nvidia are probably flashing their widest pearly-white
smiles from all the green bucks the GeForce will bring into the company war
chests.
So what's the lowdown on this new graphics card that Nvidia so proudly flaunts?
The GeForce 256 incorporates many "firsts": the first 256-bit 3D processor,
the first to implement a hardware transform and lighting (T&L) engine, and
the first four-pixel rendering pipeline. The GeForce is also the first graphic
accelerator to take advantage of Microsoft's new API, DirectX 7.0, which features
cube environment mapping, projective textures and vertex-blending. The GeForce
256 has nearly 23 million transistors in it, more than twice the complexity
of the Pentium III processor.
In english please…
When computer games create a 3D scene, the process is divided into two main
stages: geometry/lighting and rendering. Before the GeForce 256 chip, all
the floating-point-intensive math that converts the coordinates of an object
into coordinates for its position in the scene is done by the CPU. The graphics
card then takes over as it draws the scene, creating the triangles and filling
in those triangles with textures.
With a GeForce accelerator inside the computer, all that math is done by the
video card rather than the CPU. Because the CPU now has a lighter workload,
game designers can now flood the video card with highly-detailed 3D scenes
and objects, and with lighting is more complex. The added details and the
complex lighting translate to more realistic environments like mist or fog.
A character's face, for example can be made more realistic with 3D noses,
eyes and ears instead of artwork.
Does it work?
Most of GeForce's new technology will not be noticeable in games using old
3D techniques. Games will need to be written specifically to take advantage
of GeForce's geometry acceleration. Up to now, all games use what is called
a software T&L engine. The new DirectX 7.0 API will support GeForce's hardware
T&L through Direct3D.
Actually, implementing hardware T&L equation on games can be very tricky.
Games will need to use higher polygon counts for users with hardware T&L acceleration,
but still the game designers must not forget the users of lower-end systems
- they need low level details as well. It's a delicate but necessary balancing
act, because it's suicide to design a game solely for the hardware T&L crowd!
So current games like System Shock 2, for example may not appear radically
different than it does on a RIVA TNT2. But the frame rates, though will be
much faster - which brings us to the next topic, Fill Rates.
The Four Pipes
Fill rate is the speed at which a graphics card can perform the final rendering
process. One way to increase fill rate is to increase the parallelisms of
the graphics processor. The GeForce contains four pixel pipelines, compared
to the two pixel pipelines on the TNT2 or Voodoo3 boards. The added pipelines
are used for Multi-texturing, a technique that produces realistic lighting
and shadow effects. With four pipelines, the fill rate is higher because four
multi-texture passes can be performed in a single clock cycle.
Is it worth it?
If you already have a RIVA TNT2 or Voodoo3 graphics card, there's no real
need to buy an expensive GeForce card now. Though you may notice a speed boost,
especially at high resolutions and color depths, the GeForce's potential will
only shine through with games that takes advantage of its hardware transform
and lighting. Some of the new games that support hardware T&L are Messiah,
Oni, Vampire: The Masquarade, and Heavy Metal: FAKK2. Developers should be
ready to release them in the next six months. Until then, you can wait and
pray that the price of the GeForce drops because the last time we checked,
it was rather steep.
If you're buying your first PC, then the GeForce 256 is an excellent choice.
Check out the next section, Bring on the big guns! before you burn your money.
Bring on the big guns!
The GeForce is the most powerful video accelerator in the market today, and
it will probably stay that way for another three or four months. Of course,
it's always wise to wait for 3dfx's next offering, especially for those who
crave for speed rather than beauty. Don't shut the door on GeForce cards yet;
the news is that the next-generation 3dfx cards will not offer hardware T&L,
which is good news for Nvidia.
For the discriminating gamer who demands the best, the GeForce may be the
only 3D accelerator card in the industry that has hardware T&L, awesome 3D
performance and stunning image quality in one complete package.