Color banding issues after changing from Ati to nVidia.

Try a different monitor cable.

Try a different monitor.

Try a different graphics card port.

If that doesn't fix it then RMA your card.

Make sure you have the adapter set to 32-bit color depth. In theory it should be identical to 24-bit color (the extra 8 bits are used for an alpha channel - i.e. transparency). But for reasons I'm still trying to figure out, I've noticed setting it to 24-bit color causes banding as you've described.

http://www.sevenforums.com/tutorials/258-color-bit-depth-display-settings.html

Also in the nVidia Control Panel, make sure the card is using the full color range. I believe one of the video settings limits it to 16-256, instead of 0-256. If that's somehow affecting your desktop and video playback, it would also cause banding.

Did you by chance have a color profile installed using the old video card?

Sorry, I never saw your followup posts to this. Since my post was picked as best solution, I've unselected it (the editors of this site have gone on a tear lately selecting best answers to old questions).

I'm at a loss as to what could be causing your problem. The only thing that comes to mind is - do you have the regular 2407wfp, or the 2407wfp-HC? The latter one supports a wider color gamut. If it's in the wrong mode, it could be mapping the RGB values from sRGB color space to Adobe RGB color space, losing some of the bit resolution in the process which could cause banding (e.g. 255 -> 183, 254 -> 182, 253 -> 182, 252 -> 181, etc). The browser might not be affected because most browsers are not color space-aware, so it would do a direct mapping of RGB values from sRGB (255-> 255, 254 -> 254, 253 -> 253, 252 -> 252, etc). But I would expect the opposite symptoms you're describing since Windows by default doesn't try to do color management.

If you have the HC, I'm not familiar with the Dell wide-gamut monitors. But most such monitors have a button or switch that lets you put it into sRGB mode (use AdobeRGB mode only for graphics work which requires the larger gamut). Most wide-gamut monitors use 10-bit panels to minimize this effect, but from a quick Google search it appears Dell used an 8-bit panel in the 2407wfp-hc. So you should expect banding viewing sRGB images with a color space-aware app while in AdobeRGB mode.


Video cards come with something called a LUT - look up table. It simply maps RGB values from the ones used internally, to the ones sent to the monitor. An ICC profile is what's used to program the LUT with the correct values. So say before calibration, a 240 or higher red value sent to the monitor might show the deepest red the monitor is capable of displaying. The ICC profile will program the LUT to convert a 255 red value to 240 sent to the monitor, with the lower values correctly mapping the 0-255 internal values to the 0-240 the monitor is only capable of displaying from the inputs.

This could be causing your problems if you've got a bad ICC profile installed (one which really stretches your monitor's range), or the monitor has bad hardware RGB settings requiring a lot of stretching by the ICC profile to correct the colors. If you've got a colorimeter and software which has a white point mode, try tweaking the monitor's native R, G, and B levels in the monitor's settings so the white point is true white. That'll minimize any stretching caused by the ICC profile. But if there is no ICC profile, the card should be sending the RGB values directly to the monitor, bypassing the LUT.

Unfortunately, Windows' support for ICC profiles has always been half-hearted. There was a bug introduced in Win 7 where any user elevation prompt (which darkens the screen) would dump the current ICC profile. This bug has remained unfixed through Windows 10, and it's been up to color profile software and video drivers to work around it.

After extensive research once a month when I attempt a blur or similar in photoshop, I would put money on this being the answer. The solution is simple then : Buy an ATI.