I have a Dell Venue 8 Pro 5830 running up-to-date Windows 8,1. A recently applied update to the HD Graphics driver (10.18.10.4176) made the system unusable, as the screen refuses to wake after sleeping. The backlight goes on but nothing displays, and only a forced power-off reboot can bring it back. No changes to power settings etc will help; only a rollback to 10.18.10.3306 fixes it. This problem has also made it impossible for me to use the Windows 10 preview, as installing the preview forced the driver update. Please help.