When a user calls to say his system is dead and nothing shows onscreen what is one good suggestion you can give for him to troubleshoot the problem?

One good suggestion is to ensure that the monitor is properly connected and powered on. The user should check the power cable and the connection between the monitor and the computer, making sure they are secure. Additionally, they can try connecting the monitor to a different computer or using a different monitor with their system to determine if the issue lies with the monitor or the computer itself.