Also note that most monitors are not wide gamut displays, and can't even display all of the sRGB color gamut, much less the Adobe RGB color gamut.
You'll find some reviews of monitors here:
If you want a wide gamut display, you'll need to move up to a better panel type (for example, IPS or PVA), and the vast majority of panels are TN now.
Even with a better panel type (IPS, PVA or one of their variants), a monitor may still not be designed as wide gamut. You have to look at each one on a case by case basis.