In our benchmark Radeon X1800 XT with 512 MB was faster than GeForce 7800 GTX with 256 MB. Period. However, our comparison has a flaw: the difference in the amount of video memory available. We will need to wait until Radeon X1800 XT reaches the market to get one 256 MB board from one of the ATI partners in order to compare apples to apples. Of course ATI is only sending 512 MB models to the media to be reviewed, so they can achieve higher scores.

What we’ve seen on both 3DMark03 and 3DMark05 is that the performance difference between Radeon X1800 XT and GeForce 7800 GTX increases when high image quality settings are enabled. Without image quality settings, Radeon X1800 XT was between 6.88% and 9.14% faster than GeForce 7800 GTX on 3DMark05 and between 3.22% and 6.16% faster on 3DMark03. When we enabled 4x anti-aliasing and 4x anisotropic filtering, the performance difference between these two cards raised to 12.16%~22.12% on 3DMark05 and 10.68%~19.78% on 3DMark03, both in favor to ATI’s new chip.

Also, the higher differences were obtained at 1600x1200, suggesting that Radeon X1800 XT is better than GeForce 7800 GTX when running on very high resolutions with very high image quality settings enabled.

We can come to this same conclusion by analyzing the results from Far Cry. While the performance difference was up to 6.25% (in favor to ATI’s new chip) in all resolutions and settings, the performance gap jumped to 23.72% at 1600x1200 enabling very high image quality settings.

Even in Doom 3, a game where nVidia’s advantage is notorious, Radeon X1800 XT finally could close the gap between these two companies; GeForce 7800 GTX was faster only at 1600x1200, and only by a small amount (4.26% at low quality settings and 5.41% at high quality settings). On the other resolutions both cards achieved the same performance level.

Once again, we could say that Radeon X1800 XT is really faster than GeForce 7800 GTX, but since we compared a 512 MB card with a 256 MB one, these results are not final.

Another issue is the fact that this video card will reach the market only on November 05th, 2005, so even though we already posted this review, you cannot buy it yet.

As a side note, GeForce 7800 GTX model from XFX we included in our comparisons is factory-overclocked, running at 450 MHz (instead of 430 MHz) and memory running at 1.25 GHz (instead of 1.2 GHz). The performance differences mentioned above refer to GeForce 7800 GTX model from MSI which uses default clock configurations.