It means the signal input from your PC is 85Hz – outside the range that the monitor can display. New Generation LCD intelligent monitor capabilities temporarily override the overscan, providing you with 10 minutes to reset timing to recommended settings. Here's how: Go to your Windows Start menu. Select Settings, then Control Panel. Select Display. Move to Settings and click on the Advanced button. Under Adaptor, change the refresh rate to 56~75. You have 10 minutes to complete the operation; if you do not complete within 10 minutes, power off and re-power on monitor to enter changes.