I'm not sure about changing all Colour Management to True Colour. But here is an issue I had a problem with.
I discovered my monitor was using a Colour Profile called 831WS (or something!). Now, I know windows uses the sRGB IEC61966-2.1 as its Default Colour Profile. So I changed the monitors colour profile and things have improved, but I still think the fringing is because Windows is taking your quality PNG / BMP image (which don't have fringing) and converting and then using a crappy JPG copy instead.
To change or check the colour profile, GoTo:-
Control Panel\All Control Panel Items\Display >> Change Display Settings >> Advanced Settings >> Colour Management Tab >> Colour Management... button.