How do i do a reboot back to factory setttings e521

I researched your question and found this information on Dell's website it explains in detail how to restore your computer. Step 4 of the article is what you need to do the restore. I suggest you either print this out for use later or at least write down the instructions because once the restore procedure starts you may need the instructions to complete the restore. Either click the link below or copy and paste it in to your web browser to take you there. Here is the link:

http://support.dell.com/support/topics/global.aspx/support/kcs/document?&docid=DSN_339949&isLegacy=true#Issue4

I hope this helps you out and if it does please answer YES on the web page you read my response on. Thank you.

In motherboard, there is a reset Jumper . Check from the manual.