Check the monitor cable connection. Look at the end of the cable and check for any bent or pushed-in pins. Plug the monitor into another wall plug. Try connecting to another system to see if it functions the same. Electrical interference from other devices such as televisions, radios, microwave ovens, etc., can cause your monitor screen to jump or shake.
Interference can also make the display appear blurry or fuzzy.
If the system is close to a fluorescent light, turn the light off or move the light away from the monitor to see if the video clears up. Consult your monitor's user's manual to see if your monitor has that capability. Q. My screen saver does not come on all the time. A system modal dialog box requires user input before the system will continue. Quit the program that is preventing the screen saver from running.