I got my U2410 a couple days ago. On the factory calibration report, the chart labeled Gamma is really a luminance chart. Don't expect a straight line at 2.2, this is not gamma per se but luminance in cd/m2 on the Y-axis vs gray level (0-255) on the X-axis, and it is supposed to look like an exponential curve, OK? Depending on the calibration software you use, you may see IRE on the X-axis vs luminance in ftL on the Y-axis. It would have been nice if Dell had also shown the ideal luminance curve for a gamma of 2.2 on the same chart. So, if your gamma doesn't track 2.2 closely, your luminance curve will deviate from the ideal one. If gamma is >2.2 your luminance will be too low, and if gamma is <2.2 your luminance will be too high (at any given gray level). Grayscale tracking looks nice and flat but at 7000K rather than the 6500K standard. I have no idea why they calibrate with a 7000K target. I know some software lets you calibrate using the monitor's 'native' color temperature, maybe that's why. The report doesn't even tell you what preset the grayscale tracking and gamma charts correspond to ... I'm sure they're different with different presets. I know zip about AdobeRGB standards, just sRGB ... I'm more used to calibrating plasma TV's with a robust Color Management System (CMS) like on the Samsungs. The DeltaE on my charts is quite good, it's consistently <2 in sRGB, and <2 in AdobeRGB except for Gray7, Red3 and Green3 where it's more like 3.75. The charts still have text saying Avg DeltaE < 5.0 but the actual results are better than that, so I think that Avg DeltaE < 5.0 is just the calibration target.