Not getting full color resolution in Photoshop

I have a problem. Even though my screen is at 32bit color depth it doesnt seem I have full color resolution. Colors arent blended properly - gradients are "jagged" and when I desaturate photos they lose a lot of nuances. I have checked the image and its using rgb/8 (correct right?) and not cmyk or anything else. In color settings I am using "north america web/internet".

What else can be wrong? Also, can a single layer be cmyk, and if so - how do I check this and convert it back to RGB? Thank you!