I had an old hard drive around, so I installed Ubuntu to it. I installed the latest kernel from that link (v4.8-rc5), and the bug is fixed there. I haven't installed the NVidia proprietary drivers.
$ uname -a Linux bruno-mitsai 4.8.0-040800rc5-generic #201609041832 SMP Sun Sep 4 22:34:01 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 16.04.1 LTS Release: 16.04 Codename: xenial ** Tags added: kernel-fixed-upstream kernel-fixed-upstream-4.8-rc5 ** Changed in: xorg-server (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1585329 Title: Sometimes a black rectangle appears briefly under the mouse cursor To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1585329/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs