I've been unable to find out what is causing a mouse cursor lag when I'm using my Win7 laptop connected to a 1080p TV via HDMI.
The symptom can be described as the cursor feeling 'heavy'. When I'm using the TV screen as an extension to the desktop, there is no lag on the laptop side of the desktop. It does not feel like a refresh rate problem: for example scrolling a big web page on the TV side is pretty OK.
Strange huh? Help appreciated!