NVIDIA GeForce 6800

Architecture and Image Quality

Its 12-Pixel pipelines and lower core and memory clock speeds means the 6800 won't perform quite like either of NVIDIA's or ATi's flagship parts, but its peak fillrate and memory bandwidth are respectable considering the 6800's price point.  At 3.9GTexels/s, the 6800's fillrate is slightly higher than the GeForce FX 5950 Ultra and the Radeon 9800 XT.  With a maximum of 22.4GB/s of available memory bandwidth, however, the 5950 Ultra and 9800 XT have a distinct advantage over the GeForce 6800.  As you'll see a little later though, the 6800's performance is every bit as good as a 5950 Ultra...

Screen Shot Comparisons
Whip Out The Magnifying Glass!

6800 No AA


6800 4X AA


6800 4X AA/8X Aniso


6800 4X AA/16X Aniso


6800GT No AA


6800GT 4X AA


6800GT 4X AA/8X Aniso


6800GT 4X AA/16X Aniso


X800 No AA

X800 4X AA

X800 4X AA/8X Aniso

X800 4X AA/16X Aniso

The group of screen shots above are of frame 5000 from the Aquamark 3 benchmark.  We set the resolution to 1024x768, and took these shots at the four different configurations we used for most of our benchmark testing (No AA, 4X AA, 4X AA + 8X Aniso and 4X AA + 16X Aniso).  If you open up multiple images and switch between them quickly (paying attention to the file names in your browser's address bar to keep track of which shot you're looking at), you'll see very little variation from card to card.  If we zoom into the images, however, it's easier to pick out some of the subtle differences.

 

 


6800 No Ansio (300%)


6800 4X AA/8X Aniso (300%)


6800 4X AA/16X Aniso (300%)


6800GT No Aniso (300%)


6800GT 4X AA/8X Aniso (300%)


6800GT 4X AA/16X Aniso (300%)


X800 No Aniso (300%)

X800 4X AA/8X Aniso (300%)

X800 4X AA/16X Aniso (300%)

This group of screen shots represent a 300% zoom of the center of the full scene.  As you can see in each shot, with Anisotropic filtering enabled, much more detail is brought out in the hill at in the center of the image.  It's nearly impossible to see any differenced between the 8X and 16X aniso shots though.  When comparing one card to another, there are virtually no differences between the three different settings on the GeForce 6800 cards.  Comparing a 6800 with the AX800 Pro/TD reveals a bit more detail on the 6800s.  NVIDIA's Anisotropic filtering seems to be a tad better than ATi's at the moment.

 

 


6800 4X AA (300%)


6800 4X AA/8X Aniso (300%)


6800 4X AA/16X Aniso (300%)


6800GT 4X AA Aniso (300%)


6800GT 4X AA/8X Aniso (300%)


6800GT 4X AA/16X Aniso (300%)


X800 4X AA (300%)

X800 4X AA/8X Aniso (300%)

X800 4X AA/16X Aniso (300%)

We also zoomed into a different portion of the screen to spotlight some differences in each card's anti-aliasing technique.  When we enabled 4X anti-aliasing, the antennas above the station and the edge of the track at the right are cleaned up considerably.  Once again, there were virtually no image quality differences between the two 6800s, but the X800 Pro produced a slightly different image.  The X800 Pro seemed to do a slightly better job at cleaning the jaggies, but it's not a major difference by any means.  With both NVIDIA and ATi using adaptive trilinear filtering, and using similar multi-sampling anti-aliasing techniques with this generation of products, it's has become much more difficult to say one card has better image quality than another.


Tags:  Nvidia, GeForce, force, 680, id

Related content