Run the diagnostics outside of Windows -- F12 at powerup.  If no errors arise there, you're set.   If one does, such as a clock battery failure, etc. - then take appropriate action.  Don't rely on the PC Checkup software -- which is not as reliable as the Dell diagnostics.  
Dell Inspiron N7110 running Windows 7.  When Dell PC checkup runs, it shows RTC Accuracy Test Fail with an error code of WSB01-HKM.  However, I have no symptoms or problems I'm aware of.  Does this indicate my battery needs to be replaced?  Since no symptoms, is this in the early stages of failure?  Suggestions?  Thanks.
RTC Accuracy Test Fail