The display resolution of the GUI changed when I was following up the official tutorial to load and render an ex2 file named disk_out_ref.ex2. Every time I hit the Apply button, things goes weired.
It worked! Thanks!
I just upgraded my driver to 26.20.100.6913 last month. The upgrades are managed by Lenovo Vantage so I have no idea how to downgrade the driver. I installed version 26.20.100.6709 which overwrote the existing one and paraview now works fine.