zoom tool in ACR

Hi, in ACR 13.0.2.644 the zoom tool is not allowing me to click and drag a specific section of the image to enlarge. it only allows 1 step zoom and back to the entire image using mij wacom pen or track pad. I'm not using hardware acceleration as it makes the zoom annoying to me, I dont want to hold the button to zoom in and out by moving the wacompen, I want to click and drag to indicate which part I want to enlarge. Is this not possibe anymore?