Hi,
I have just noticed this, and I don't know at all what I did that could have caused this very annoying thing :
With every visual styles but mine (base / non-base / named "aero" or not) :
Normal DPI
Now with my vs :
DPI = 15 000
My advice : check it regularly while developing yours.
(Please don't hesitate to show me a direction where to look for in order to fix this...)