Latitude 5285 random reboots

I had the same issue with my 5285, random crashes even when the PC wasn't hot. Very frustrating. I installed Ubuntu and while my camera and fingerprint reader don't work yet I do not have random restarts anymore. No real fix found sadly

So, since the system was delivered and I’ve set it up it has turned off on me twice, while I was using it. While I thought it might be a software issue since it showed up on two separate computers, I have reconsidered my thoughts on the issue and still believe it to be related to hardware and here’s why:

1. The software configuration I have works fine on ALL the other computers I have as well as those of the people I work with. From a Dell XPS L502x to a XPS 8900 to an Inspiron 7558 to a Latitude 7250. None of them exhibit this issue when using Office 365 x64 or Power BI Desktop.
2. Just because the issue shows up on two different 5285’s doesn’t mean it can’t be a hardware issue. It just means it’s not a defective part or defective unit type of hardware issue. There could still be a design flaw that slipped through QA and system validation.
3. The biggest reason I find to still believe it’s a hardware issue is this: It doesn't exhibit symptoms of a software issue. The system doesn’t blue-screen, dump memory or leave any traces that something went wrong while performing a software operation. On the other hand, there are plenty of indicators that is a hardware issue.
4. 1. It is a hard reset. It behaves exactly the same as if you pressed a hardware reset button. I’m not sure if the system loses power completely and performs a cold boot or simply does a warm boot, but I know that the reset is instantaneous – thus no blue screen or saving state.
   2. The OS gives no automatic indication of recovering from anything. It merely logs a Kernel Power Event 41 Task 63 (The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.)
   3. I am unaware of any software issue which can physical cause a reset this cleanly without the OS catching it…

Sorry that you guys are experiencing the same issue as I have been. However, this may be of some help. Since I last posted I was able to take one action that has, to date, averted the random restarts. That was to disable the enhanced C States in BIOS.

To do this:

1. Restart your computer and press F12  before the Dell logo appears.
2. When your menu comes up chose: Other Options: BIOS Setup
3. Select the Performance menu
4. Select C States Control item
5. Uncheck the box next to C States
6. Apply settings and restart.

I can't promise that this will fix the issue for anyone else, but I can report what I have observed with my own 5285. 

• I haven't had a random restart since disabling this option which was two weeks ago. This is by far the longest period of up-time that I've observed in my personal experience with either of the two 5285's I've had in my possession. (Until it goes another couple weeks / months I still won't be completely certain that this is a genuine fix though.)
• During that time, I've used my computer the way I intended to use it when I purchased it. I loaded all the software I need for work and home including Office 365 x64 and Power BI Desktop x64 and have used them successfully each time I've needed to. That means, I've used the computer for 8+ hours a day during the weekdays and each day during the weekends without a random restart.
• I haven't observed any significant battery life drop or performance loss with the C States disabled.

Two weeks is by no means conclusive evidence that the issue has been eradicated so I'll keep posting on whether or not it manifests itself again.I just figured I'd share my latest findings in hopes that it might help someone else get past this completely exasperating problem. 

-Paul

Hi Paul,

 many thanks for your advice.

 I will make the changes to the BIOS and see what happen. I will let you know how it works for my 5285.

 Regards,

  Roberto.

Hi Paul

Even my system also behaving the same way. I have Office 2016 installed and the random reboot without any warnings as well as no blue screen.  As you suggested I have made the changes to BIOS.  Will keep this form updated about the stability.  The random reboot even after the latest BIOS update from DELL.  The latest update was released on 3/18/18.

Thanks

Hi All,

 even in my case the problem has not been solved.  Still having reboots several times.

 Roberto.

Thanks for the reply Roberto. Sorry you're still experiencing the random reboot issue. Here's what I've been up to.

After I disabled C States on the 1.1.12 BIOS I was able to successfully run without any random reboots for over a month. At that point I noticed that BIOS 1.3.4 had come out with this intriguing line in the notes: Updated to the latest CPU microcode to address CVE-2017-5715 and associated Intel Reboot issue. Googling this turned up some very interesting data and seemed like it could be the real potential root cause of my original random reboot issue. Because my system was running well I waited another week before finally deciding to update my BIOS to 1.3.4. I did update it and left the C States disabled and observed the system for several days with no random restarts. At this point I had to see if the problem was truly corrected by the microcode update, so I re-enabled C States and kept using the system. Fortunately, I still didn't observe any random restarts. I later updated to 1.3.5 and still the system has remained stable. I can't say for sure that it's "fixed" yet as I just haven't had enough up time since re-enabling C States to be confident that it won't randomly restart any more, but it is definitely trending that way. I'll be sure to post here if I do see the issue return.

I should also mention that now that I've been using the 5285 with C States enabled I realize that I was pretty off in my original observation that disabling them didn't adversely affect the battery life. I'm now getting about 2x the battery life during a normal work day where it is used off and on throughout the day (not as my main driver). This is precisely where they should be impacting the system. 

Just thought I'd update...

Paul

I try to enable the C-STATE, but the reboot started within 2 hours of enabling it.  Now I am back to disable it again.  I am on 1.3.5  BIOS version. I do agree that disabling C-STATE does drain the battery.  I get only 5 hours on the full charge.  But if I enable it, the reboot happens on its own.  

I'm having the same problem : random reboots.

They exclusively happen when the computer is not connected to my dock though (WD15)

So, one more update about my Dell. C state is disabled (i.e., latest and default BIOS settings), Windows and all Dell updates performed (up to 25/04). No good news but bad news, it seems that the frequency of reboots has increased. The problem is when the PC is under battery power and it happens using any program. In my case is not a reboot but an immediate shutdown. During my last shutdown I was updating Visual Studio 2017 and, as a result, the installation was corrupted. I’m very disappointed.

Roberto.

Seems like disabling C-state removed the problem but also rose  the battery usage a lot.

Are these faulty processors ? when searching for c-state reboot on internet, it seems like it

Has dell an opinion on this ?

A quick update on my end. I also had to disable C-States again in BIOS even with the latest release. It seemed fine for a while and then, it was back on a pretty regular basis. As far as an official thought from Dell, I'm not 100% sure. As I had explained before I got a whole new 5285 and saw the exact same behavior as before. When I worked with the Dell reps, they said that disabling the C-States was going to be the "official" solution to the issue. Not sure if I buy that yet. I don't believe I should have to disable a key feature of my hardware to get it to work right. It should work correctly with all features enabled. I just haven't decided if I should try to push for a 5290 as a replacement...

The answer basically being "to use your tablet computer on battery, you need to disable power saving features" ...

Maybe dell can work out a driver or firmware update to prevent this

Other rant : I hate to lose my message because the forum requires me to login. Why do I go back to the home page after a login ?

I had my CPU/MB replaced and now it's working correctly, no more random reboots !