I was using my gumstix overo on a summit board with a monitor plugged in.  While using it the monitor blinked and then went out, since then I can't get any video from this gumstix.  I have tried a different cable and a different gumstix, and everything else works, so I believe its the summit board or the overo COM.

Is there a diagnostic I can do or do I need to send this back to Gumstix?

Thanks