Random screen locking

I just installed 11.1 on a Dell Inspiron E1705. For the most part, it works well (I even got my wireless adapter working). The one problem I’m having that is more frustrating than anything else that the screen locks randomly. The power cord is plugged in so I know it isn’t a matter of a dead battery (despite seeing a pop-up that says “Power Management”) when it happens.

I’ve turned off as many options in kpowersave as I could find which relate to screen locking and have even turned off acpid but I’m still having the problem.

Any help will be appreciated.

I am having the exact same issue on an Inspiron 1720. The issue appeared around 3/11 patches. Is anyone else experiencing this?