INTRODUCTION
How does playing Doom 3 at High Quality, 1024x768 resolution, 4x anti-aliasing /
8x anisotropic filtering OR at High Quality 1600x1200 without
anti-aliasing or anisotropic filtering at 45*
frames per second and 42* frames per
second respectively sound?
Now, how does that sound coming from not a $499 video card...not a $399...not
even a $299 video card...but $199 and $149 video cards sound?
* Results from running timedemo demo1 in Doom 3
Welcome to the new
mainstream video card offerings from NVIDIA. Known prior to now as the NV43
chipset, today we are introducing you to the NVIDIA GeForce 6600 series
comprised of the 6600 and the 6600GT. Actually a third card (not an NV43 but
rather NV42) has some brief
mention by NVIDIA, that being a 6800LE which will be an 8 pipeline,
256-bit data bus product. The 6800LE is not within the scope of this
preview but we'll be sure to cover it in the future.
NVIDIA's GeForce 6 Series
HI-RESOLUTION IMAGES I know most of you want to see some eye candy so let's get that out of the
way first before moving on to the details.
Click on any of the images below
to view hi-resolution versions.
One thing that should really jump out at you (it
did to me at least) is that all of the GeForce 6600GTs will be SLI-ready. What
does this mean? Well it means that for roughly the price of a single
6800GT you could have two6600GTs! NVIDIA appears to be
sticking to their claims (as was originally announced with the 6800 series in an
SLI config) that an SLI configuration will come close to doubling your 3D
acceleration power.
Needless to say, there will be a new twist on video
card reviews from now on:
"Hmm, I wonder what will run Quake 4
or Half-Life 2
faster...two mainstream NVIDIA video cards in SLI mode or a single enthusiast
card?"
AVAILABILITY & PRICE So great! This is some really cool news but quickly the question becomes
"when can I buy one and for how much". Well as stated earlier you can see that
NVIDIA is aiming for the 6600GT and 6600 to cost $199 and $149 respectively. As
for availability the current timeframe is the end of September for the
PCI
Express versions and likely another month or so for the AGP versions.
An
interesting point regarding availability is that NVIDIA does not necessarily
have total control as to when their products will appear on store shelves. The
retailers have a substantial stake in all of this too and so they play a large
role in the entire availability process. In other words, it's not so simple as
to being 100% up to NVIDIA as to when you see their latest products on store
shelves.
NVIDIA is putting a strong emphasis on the penetration and then saturation of
SM3.0/ capable hardware into the mainstream market. The sooner this happens,
the better, for all of us. It should be a well known fact that game
developers have to take into account the greatest market share of customers.
Today that includes a large chunk of consumers that still have GeForce2-class
cards that they game with. The sooner those folks upgrade to a SM3.0 capable
video card the sooner we will reap the benefits of truly next generation gaming.
Along with this direction that NVIDIA is taking
comes the importance of the OEM market. This will be the initial focus for
NVIDIA in order to effectively and quickly achieve their goal of changing the
landscape of the antiquated video card base that exists today.
PERFORMANCE The last thing to touch on in this preview is that of performance. NVIDIA
did not provide us with any sample 6600 or 6600GTs to test with so all that we
can do is share with you NVIDIA's in-house test results. Rest assured, however,
that once we do have these cards in hand a review will be soon to follow.
It should be noted that
the following two graphs establish an ATI X600XT as comparison as well as
presenting it as the x-axis baseline. In other words, the ATI X600XT in the
graphs below represents the baseline to NVIDIA's 6600GT percentage gains over
it. Also, these graphs are not very readable at the size shown below so please
click on them for the full size graphs (~120KB each).
NVIDIA's Doom 3 Percentage Gain Graph
NVIDIA's Game Variety Percentage Gain Graph
ULTRASHADOW II Now, for the first time, NVIDIA's mainstream product line will boast the
UltraShadow II technology.
UltraShadow II technology is in place on the 6800 product line and you can
find many detailed articles on it which we'll not get into here other than to
outline a few main points.
Single pass shadow volume rendering
doubles the performance
Intelligent culling algorithms ignore
shadow pixels that aren't visible
Combined with Intellisample 3.0 to
ensure shadow edges are properly
aliased
In other words,
UltraShadow II technology is not a singular "all or nothing" approach. It
is comprised of various parts, some of which can be enabled/disabled by the
developer as necessary. One very current example is that Doom 3 (while making
use of some parts of
UltraShadow II technology) actually does not implement depth bound testing in the current NVIDIA drivers.
Programmers can define a subset of the scene
(within z-min and z-max) to limit lighting/shadow calculations to the
appropriate area for each light source. Z component of the window-space bounding
box reduces the area that needs to be checked.
UltraShadow II - Implementing Depth Bounds
In the series of images below you can first see a
scene with a lot of lighting and shadows at play. The second image points out
the visible geometry and the last image shows the shadow volume geometry.
Clearly, the shadow volume geometry is much greater than that of the object
geometry and
UltraShadow II technology affords excellent performance because shadows are
not textured. Therefore, both shadow shaders can be sued for shadow calculations
at the same time.
UltraShadow II - Example Scene
Dramatic chase scene with shadows
Visible geometry
Shadow volume geometry
Images courtesy of Contraband
Entertainment
VIDEO There are also some very interesting improvements regarding video quality in
both encoding and decoding processes. This will be touched on in more detail in
an upcoming article so for now I'll present you with some interesting
screenshots to pique your curiosity. In the shots below the first image (with red
circles) indicates the current state of video. In the following shot (with green
circles) indicates the improvements now made available by NVIDIA.
Vertical Scrolling Text GeForce 6600
De-Interlacing
CONCLUSION The NVIDIA GeForce 6600 and 6600 GT quite possibly offer more to the
mainstream consumer than any mainstream video cards ever have before. In the
past, advanced technologies like
UltraShadow II,
Intellisample 3.0 and the latest
Pixel/Vertex Shader Model support were reserved for the enthusiast
market...now, that has all changed.
NVIDIA is making a statement today
with the GeForce 6600 series in that mainstream consumers will now have all of
the major features that their enthusiast cards have always had. There obviously
has to be something that allows room for the price difference in market
segments. That something is the reduction of the bus width down to 128-bits
(instead of 256 on the 6800 series cards). Also, these cards have half the
pipelines (8) than that of the 6800 GT and 6800 Ultra (16). Pipelines are not
everything though. One only has to look at the 500MHz core and 500MHz (1GHz
effective) DDR3 memory of the 6600 GT and know that it could be one heck of a
performer for the price.