Viruses come in many different forms and flavours. While some viruses are outright malicious, looking to destroy your computer and all of the files contained therein, others are just bothersome. Computer screen flickering viruses fall into the latter category, presenting nothing more than a moderate nuisance. The easiest way to remove these viruses is to restore your computer to a state before the virus was present on the hard drive. This can be accomplished with the System Restore utility.
Navigate to the "System Restore" utility by opening your computer's "Start" menu, going to the "All Programs" list, opening the folder marked "Accessories," and opening the folder marked "System Tools."
Select the option to "Restore my Computer," then choose your restore point from the list that appears on-screen. Select a date prior to the first appearance of the flickering screen virus, but not too much farther back than that.
Restart your computer to complete the system restore procedure. Your computer will then load all of its past files into memory during the start-up procedure, so expect it to be at least five or 10 minutes before you get back to your desktop.