I have two Dell U2713HM monitors and been experiencing the exact same issue as stated in this thread http://en.community.dell.com/support-forums/peripherals/f/3529/t/19495965.aspx. I went through the troubleshoot and diagnosis step you posted and weren't able to resolve the issues. It keeps coming back on both monitors, usually at different types. The only way to resolve it temporarily is to turn them off over night, which keeps me away from being productive.
Here is a video recording of it happening on one of the monitors.
Please advice on how to get replacements.
(Please visit the site to view this video)
Thanks.
