Instead of using the slider in the Display Properties\Settings tab, try setting the resolution in Settings\Advanced\Adapter\List All Modes... Select the desired resolution and Apply & OK it right there in the Adapter tab (before exiting to the Settings tab)... this works when setting a higher resolution in Safe Mode where the 32bit display driver is not available, and the setting is not supposed to work, so it stand a better chance of working in normal mode... and if it doesn't, reinstall/update the Display\Video driver....