For XL2720Z monitors, firmware Version 2 or later is required for Blur Busters Strobe Utility.A) Either get a new BENQ XL2420Z or XL2720Z with V2 Firmware preinstalled; B) Or send into BENQ for free upgrade.
This will erase all installed software and data loss will happen but it will fix Nvidia installer failed error as you are literally resetting everything by reinstalling the entire OS.
These files can conflict the installation process and you need to delete them permanently before installing the new/updated drivers. Delete the files/folders permanently (even from Recycle Bin) if present and reboot the device.
You need to enable “Show hidden files, folders and drives” to see few of these files/folders.
In case if you are still getting the Nvidia installer failed error, then disk space is not the culprit and continue troubleshooting the issue.
Nvidia installer failed error can also occur if any Nvidia processes are running in the background while installing the drivers.See BENQ America press release for info; C) Or install via Linux with no hardware tools, see forum thread; D) Or manually install the V2 Firmware yourself from Windows, by following the instructions below.software (ISP Utility).