Change Color Calibration (Dell U2410)

The color on my Dell U2410 looks washed out. I tried to calibrate, but it doesn't take effect. I tried the advice here: http://embdev.net/topic/284710#3027030, but that didn't do anything either. The screen is hooked up with a mini display port to dvi connector (however, I have it running to hdmi with a converter cable). Not sure if this is OS X, the cables I'm using, or the monitor. Has anyone been able to shed some light on this issue?