CMYK (Cyan, Yellow, Magenta, and Knockout)will display differently from one monitor to another for one simple reason. Monitors are calibrated to display RGB. The standard CRT monitor as you already know uses the red, green,and blue colour gun, and as such cannot properly display CMYK no matter what gamma settings you are using. Every ones eyes see colour differently. set your gamma in the morning, then set it again a few hours later, you will see that change for yourself. The standard ICC profile settings in PhotoShop (SWOP) V2 only represent a standardized working space for attempting to maintain colour consistency. The operative word is "attempting" There is only one way, ok two ways to ensure exact colour. Specify Pantone ink colours to be used once seperations are made, and the other swear up and down that it was meant to be that way.