I love quoting myself.
Sorry, my mistake..!!
Did you try the un/reinstall by Tech..??
Please try this. (with the uninstall utility..!)
asyn
I uninstalled with utility/rebooted, still no graphics card. Deleted /uninsalled graphics card.
Installed latest version of Avast and re-installed Graphics card and drivers.
Avast works but i still get screen signal loss after the Windows 7 boot screen but before the password screen is displayed.
Me thinks this could be a serious problem.