I too would suggest you get the latest drivers and install them and then check results. If the problem continues, swap the monitor elsewhere or place a different monitor and see what happens. You can do the usually as doing the simple cable reseating, etc. if a bad connection was to include a video card reseating as well. Come back with results. In some cases where this has happened and most often in XP installs, where the screens blanks out or flickering momentarily, it has been corrupted s/w and/or what was needed. It maybe s/w that got stepped-on and/or improper setup was used and now because the h/w can't meet those demands has weaken. try using 60Hz, vs 70Hz as example here in the video config.
HP PC 610y
Windows XP
McAfee Security
Desktop stutters, flickers on and off. Cannot click on icons. Must do hard shut down to turn off. Used system restore which did not resolve problem. Need assistance.Security scan did not indicate viruses/malware. Thanks

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