I have a rather serious shutdown/reboot issue with my Ubuntu OS on my brand new Dell latitude E7440 netbook. The issue does not seem to depend on the OS version: it occurs with 12.04, 13.10 and now with 14.04. I've waited for the new LTS in the hope that it would solve my problem, but that is not the case.
After shutting down my ubuntu, my laptop reboots about two seconds after shutdown. I've tried many things to solve it, but none of them did the job. I have the 64 bit version of 14.04 installed and boot in legacy boot mode with secure boot disabled. The behavior is independent from a power cable/usb device/ethernet cable being plugged in. Strange enough, however, it does sometimes stay powered off after being used for several hours…
I know there have been several treats concerning shutdown/reboot issues, but none of them provides an answer to my specific case. I ran diagnostics in the BIOS to recover any potential hardware problems, but there were none. If you have an answer or even a clue on how to solve this issue, it will be highly appreciated! Thanks in advance!
Best Answer
I experienced exactly the same problem on my new computer Intel i5-4440 processor and Intel DB85FL motherboard (4th Gen). First I faced this problem with Ubuntu 13.10. and subsequently after upgrading to 14.04 LTS.
I did the following recently to solve this problem of SHUTDOWN and automatic REBOOT again withing a second or two.
I have Intel Visual BIOS. On power up I pressed F2 > POWER > Wake On LAN from S4/S5.
This has 3 options. 1. Stay Off, 2. Power on - Normal Boot, and 3. Power on - PXE Boot. My computer was set to #2, which was making it automatically REBOOT after SHUTDOWN. I now changed to #1 option mentioned above. Now it is okay.
Hope this would work for you as well. Best wishes.