Two things I suggest trying.  1. Open Internet Explorer 9 and go to the tools button on the top right, next select "Internet Option" then Advanced, select Restore Advanced Setttings and also Reset Internet Explorers settings. Next install ccleaner and run the cleaner. Now try using Internet Explorer, browsing your sites and then powering down. 2. Create a new user profile and delete your old one. Go under the assumption that something is your user profile is corrupt, follow the instructions here. Also a few questions, what programs are you running on your XPS 8300 do you have anything that is a registry cleaner or something that says it will speed up your PC, if so they could be causing the problem.
I have had the XPS 8300 for less than a month.  I am having a problem with it storing history.  It will not record a history of any websites being visited.  I reset internet explorer (IE9) but that did not help.  I contacted Dell and they removed and re-installed IE and that did not help.  Still waiting on them to call me back after being on the phone over an hour with them yesterday.   I have the settings set to maintain history for 20 days and use 250 mb to story history.  Any help?
XPS 8300 not storing history