In some cases when the 'DirectX9 - Complex' test is run at very low resolutions (512x384 and lower) a flickering white band may be observed at the bottom of the test.
So far we have only seen it happen at very low resolutions and it does not appear if any level of anti-aliasing or V-Sync is selected. It appears to be a rendering issue of the 'DirectX9 - Complex' test and not related to a driver issue.
Update: Another cause seems to be running the EVGA PRECISION XOC software in the background. This tool is capable of displaying an overlay window, over the top of the normal 3D scene. This seems to cause glitches in various software.