15 DC15250, critical fan control bug (BIOS 1.6.0 & 1.7.0), identical to Vostro 3530 issue

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Ha. The situation only gets worse! 

I'm guessing that the Inspiron 3530, the Vostro 3530 and the Dell 15 DC15250 are basically the same device (which, looking at the pictures and hardware configurations, seems to actually be the case).

Also, I just found out about the movement activation thanks to you. Happens on the Inspiron too! Thanks, Dell!

Thank you Francynox for your original post. I too am experiencing the same issue with my Dell 15250 laptop, and and my own investigation led me to the same conclusion it's caused by a s/w defect introduced in BIOS update 1.5.0 or 1.6.0. Sadly I have been unable so far to convince the Dell Support Technicians who've already replaced the fan and motherboard. The replacement motherboard came with 1.5.0 installed so has the same problem.

I will update my open support case with Dell and link to your post.

My keypad gets heated up soon, just while browing the text content. Sensing heat only at the centre of the keypad. Is this the issue fan control?  

Hi @DC15250_user​ . The CPU is located roughly under the center of the keypad which is why you're feeling heat there. If you touch the bottom of the laptop you'll feel a hot spot there as well.

While the fan is not coming on due to this problem, the CPU temperature sensors still work. You can check it out by installing the free utility Core Temp 1.19.5. I'll suspect you'll see core temps maxing out at 100C before the voltage throttling kicks in to prevent CPU overheating and shutdown.

And if you're running the Dell Optimizer app, you might want to consider switching to 'Quiet' mode under Thermal Management on the Power & Battery tab. This mode really throttles the CPU so performance drops way off, but it does keep the CPU temp much lower without the fan running. Running constantly at 95C+ will shorten the life of your CPU.

@Stephen Richards​ Yes, you are right. Even at the bottom hot spot is there. 

I checked the Dell Optimizer app, as you suggested, its in QUIET mode by default. 

Sometimes the fan starts running with a noise continuously. Lifting the laptop for few seconds and keeping it down, shuts the fan off. But the heat continues through out. 

As it is just a week old/new laptop, finding all these things weird. 

What about returning the laptop? 

Exactly as @Francynox  mentioned below, when the laptop is slightly moved, the fan starts running.

     >>>>>>>>

• "Physical Movement: The fans start after the laptop is physically moved or shaken (accelerometer trigger?)."
• <<<<<<<

@DC15250_user​ , depends on what you want to achieve by returning your laptop. This problem impacts all Dell 15 DC15250 model laptops, plus any other models that share the same platform as highlighted by Fancynox. So returning it to get a replacement would be a waste of time. Personally I'm going to wait for Dell to release the workaround (BIOS downgrade) and then a permanent fix, and just manage my thermals by hand in the meantime.

@Stephen Richards​

Yes, that’s a valid point. If this issue affects all devices of this model, replacing it with the same model may not really help.

I initially considered switching to an older, stable model since I started noticing this behavior from the first few days of purchase. However, when I checked with the Dell showroom yesterday, they mentioned that no such complaints have been reported so far for this model.

So it may indeed be better to wait for the workaround and the permanent fix from Dell, hoping it will be released soon.

Hi @DELL-ChrisM2 or any other Dell employees monitoring this Community Forum. How do we get status updates and an ETA on the BIOS fix for the DC15250 and similarly impacted laptop models?

I want to reach out to some online influencers who cover Dell Hardware to see if they can help get the message out to the wider user-base and potential purchasers to raise awareness that Dell is working on a fix for a major thermal management issue across multiple laptop models. It would be good to be able to provide an ETA at the same time.

We Forum Liaison are not on the computer model teams. We do not have direct contact to the engineers. All we can do is present the data from the Forum (thread, number of users, number of replies, computer model, etc.) to them via an internal tool and wait. When we get something, we post it. The number of unique cases created through GHN (Get Help Now) is fed to the computer model teams.

Hi @DELL-ChrisM2​, thanks for the quick response - appreciated. 

Any suggestions on how regular retail customers like us can get in touch with the computer model teams? Or are the individual support tickets we have the only way?

Ideally it would be good if Dell could make a public statement and pin updates to the Community Forums as well.

@Stephen Richards​ 

Individual support tickets is the only process we know.

We do make public statements within threads as shown here. When we have a solution, we post them within the thread as shown here.

Pinned Posts are broader based subject matter.

Hi @Francynox , I have to admit that earlier I was slightly skeptical the shaking the laptop would make the fan come on, but I've been trying it for a few days and I'm convinced - it seems to have a 100% success rate getting the fan to start up after a cold boot.

I'm still scratching my head though about how it works. I couldn't find any DC15250 schematics to confirm it contains an accelerometer, but they are so inexpensive these days it's not unreasonable to assume there is one in there somewhere. The only thing I can think of is that maybe the accelerometer output feeds into the same IC and/or section of the BIOS that also handles the thermal sensors, and getting an input triggers it to also check the temp inputs, causing the fan to come on.

Anyway, to help raise awareness of this issue and maybe speed up a fix, I've reached out to a few reputable Tech publications like CNET, Techradar, PCMag, and Windows Central. Let's see if any of them are interested in the story. I'll keep everyone here updated.