Windows 10 64bit GTX 1080Ti + newest Nvidia drivers at the time.
Issue occurs in 2.79 newer daily builds (Testing at the moment d95eabf ) , 2.79 works fine.
The issue started occuring after I got a new GPU (GTX1080 Ti), with my GTX690 everything was fine.
Whenever I try to bevel something in edit mode, it doesn't take my cursor's position, instead it jumps to maximum allowed value of bevel. Usually this happens after I bevel successfully once, the second operation fails like I described.
On my end this happens with every blend file, every version.
Exiting and reopening the file fixes the issue for one operation, then the problem persists.