I'm not on a Vista machine at the moment but there is a dpi setting I've seen somewhere in a left pane.
It's in one of the options here, right-click Desktop > Personalize and have a look at the screen where the resolution is set.
Samsung Galaxy S9 review
ManvsMachine and other artists put Apple's iMac Pro to the test using powerful rendering tools
What to expect at Apple's 27 March education event
Comment filmer l’écran d’un iPhone ?