This is regarding the ME400CL (the LTE/3G version, not available everywhere, I bought mine from amazon.de shipped to the UK), so it might not relate to the ME400c but maybe worth trying. Problem: When I open the case I just get a black screen (it is not completely off, take the tablet to a dark room and I can see the backlight is still on and drains the battery quickly as it stays on). I was having this wakeup/connected standby issue randomly around 3-4 times a day and it was starting to get annoying. I have tried to solve this issue using some of the suggestions on this forum: 1. Refreshed and Restalled the tablet. 2. Turning off Wi-Fi before sleep 3. Updating the drivers from dell for the Wi-Fi. 4. Did a fresh Windows 8 image and installed the Asus driver pack. Also Tried: 5. Installed 8.1 RTM, which now includes the drivers for everything, same issues happened (this is when I started to worry this issue would not go away). This is where I had a thought I don't remember this happening when I first got the device in April, I had changed the case from a IVSO case to a MOKO slim case in June (and have probably been having this issue since then). Here is a link to the 2 cases I own: IVSO: IVSO® ASUS VivoTab Smart ME400 ME400C 10.1-Inch: Amazon.co.uk: Electronics MOKO: MoKo Ultra Slim Lightweight Smart-shell Stand Case for: Amazon.co.uk: Electronics I put the IVSO case back on and the problems have disappeared, this is after 3 days, zero reboots on the IVSO. After 2 days of working fine in the IVSO case, I changed it back to the MOKO, after about 30 minutes opened the case and the machine had crashed, had to do a forced restart. Put the IVSO back on for 5 hours worked fine, put the MOKO back on and a reboot was required after 25 minutes. As the MOKO case gets a 5 star review this may only affect the CL version of the ME400, and might be caused by the modem or overheating of something (even though it does not feel warm), it is probably the 2 strong magnets to hold the case shut causing the issue, as I checked the IVSO and it has none. Now after changing the case back the Eventlog\System logs all I see just events 506/507 entering/exiting connected standby and no forced reboots. Conclusion: If you are having issues with wakeup/connected standby and getting a black screen as quite a few people seem to be, remove the case before doing any fault finding suggestions on this forum and see if the problem still occurs. I can now start enjoying this fantastic tablet again. I would be interested to know if this helps anyone, especially if this problem occurs just on cases with magnetic clasps.