I know this may not be Windows 10 related but I have this problem. Since I updated the BIOS of my Dell Inspiron 7720 I have a weird square acting as mouse pointer after coming out of sleep mode. See attached image. The mouse pointer becomes normal after opening an app. What I tried: updating graphics drivers for the Nvidia GT 650M and updating touchpad drivers. The newest Nvidia drivers crash the laptop. Updating the touchpad drivers at first seem to help, but didn't in the end. Hope someone has a good suggestion ! Thanks.
It's obviously graphics/graphics ram corruption. The touchpad has nothing to do with it. It's just another cursor as far as the graphics card is concerned. Try turning down or off graphics hardware acceleration, disable mouse shadow, and google "graphics corruption at mouse cursor." Edit: Can you downgrade the bios back to the one that worked?
Thanks pf100. Thanks to you I found several threads about this problem and there is a nice workaround: switch on mouse trail.
I'm glad I could help. I used to have to turn on mouse trails to fix graphics corruption around the cursor on old windows 98 machines with AMD graphics cards. The more things change, the more they stay the same.