RE: Dell Precision M6800 Bluetooth Assistance
I had the same problem - no evidence of Bluetooth on my M6800 at all apart from the dead Bluetooth light above the keyboard. I had upgraded from Win7 to Win8 (my first mistake!), so I guessed the drivers were missing. I found the DW 1550 one's on the Dell driver download.
This did then get the bluetooth controls appearing, so I can now switch BT on and off (keyboard light comes on) and the BT icon appears in system tray.
But it's pants. I can't get it to connect to anything. It spotted our Bose BT speaker, and played music through it for about 10 mins and then it packed up!
When I turn it on now, it just says "searching for devices" constantly and never finds anything (even when my phone and the speaker are set to discoverable (phone can find speaker if I give up and connect that instead).
I am going to try again with the latest drivers, so I am sorry this is only a partial solution, but I thought that might be of help if you're still stuck.