cate, you can check it in a few ways. Use a multimeter and the barrel of your AC adapter. The positive lead is the inside barrel and the outside is the negative. Plug your adapter in and see if you have output, you should get something in the 19 volt range. Move the cable /barrel around a bit, just to make sure the wire is not broken on the inside of the barrel. If you continue to get power, the adapter is okay. Then "you do have to take it apart and expose it and see exactly what you need [guide|719] shows you how to get it all apart. I would try to either get it from [http://support.dell.com/support/edocs/systems/xpsadamoXPS/en/sm/sysboard.htm|Dell] or one you have the part check on [http://www.digikey.com/?gclid=CLififTznqcCFYXD7QodzEujPg|Digikey] or [http://www.mouser.com/Search/Default.aspx?Stocked=False&RoHSCompliant=False|Mouser.com]" The DC jacks are also available on ebay, but will run at about $20. If your jack still has all the leads on it, you may try to resolder it and see if that will make a difference. Either way, this job does require soldering skills. Hope this helps, good luck