Image quality comparison

As we mentioned in Part 1 of our Quake 4 High-end Shootout article, ATI has developed a new driver for the X1000 series of cards that reprograms the logic within the VPU’s memory controller in order to more effectively handle memory accesses.

In a nutshell, with this new driver ATI has basically tweaked the way memory read/write requests are prioritized in order to improve performance specifically for OpenGL titles like DOOM 3 and Quake 4. ATI’s old way of handling these requests turned out to be inefficient, resulting in lower performance.

In last week’s article, we found the tweaks made with the new driver improved performance dramatically for the X1800 XL and X1800 XT, but many of you wanted to see before and after screenshots to see if image quality was affected. Have a look for yourself:

Old driver

Optimized (new driver)

Old driver

New (optimized) driver

As you can see, image quality is different with the new driver; it actually looks better. Check out the difference in the wall on the left side of the map:



Old ATI driver




Optimized (newer) beta driver


You can also see a difference here:



Old ATI driver




Optimized (newer) beta driver


We have a feeling that we’ve probably stumbled upon a bug present in the older driver that was fixed with the newer (beta) driver. Image quality looks better with the newer driver in the second screenshot as well.

Now that the image quality issue has been cleared up, let’s see what kind of performance improvements the new driver brings…