XPS 15-9560, CPU stuck at 0.78 GHz, #3

I have the same issue, I did not find a solution until now...
The only guess I have is that it comes to protect the computer for some reason or it is a design limitation after some time of use of computer as it seems to be an old unsolved issue on the dell users community...

I have a very similar issue, mine (XPS15 9560 i7 32GB 1TB) can't ever get above 1.89GHz but often gets stuck at 0.78GHz and then needs to battery to be disconnected to re-set it. 

It seems to be (at least in part) a power throttling problem, (which also seems to be depressingly common on these models), but the problem is much worse since the recent updates - although hard to know which specific update might have caused it.

It happened to me before, after an update a few months ago.  I solved the problem then by doing a system restore back to how it was before the update.  I would prefer a solution that does not involve never updating my computer again!

Monitoring using Intel Ultra Tuning app shows power throttling active when it is stuck at 0.78GHz.

It seems to get triggered when the Intel GPU is doing a lot of work (the NVIDA GPU hardly seems to be active at all).  Just watching YouTube full screen is enough to cause it.

There are several online fixes involving re-applying thermal grease and adding thermal pads to the voltage regulators, undervolting the CPU etc. but this must be partly a software issue as the DELL updates seem to be creating the problem (at least for me).

UPDATE

Following the link in the original post, I opened "Dell Command Power Manager" and found that, in thermal management, my system was set to "Quiet".  Changing it to "Optimised" or "Ultra performance" has removed the 1.88GHz cap on the CPU speed.

I had this problem twice on my 9550... I was going crazy.

Disconnect the main battery, wait 1-2 minutes, press the power button, reconnect the battery and try if the CPU freq has unlocked.
If the CPU freq is till stuck you have to remove the mainboard carefully, then disconnect also the Bios battery, press the power button to discharge all the capacitors and then reassemble the XPS.

With this method I revived also an XPS 9350 which didn't want to turn on.

It seems a dumb procedure but it will save you a lot of money.

I feel your pain. I've had the same problem twice as well. The first time, I tried everything, disconnecting the battery and all that, the power thermal management thing, updating all the possible drivers, updating windows, doing diagnostic scans, etc. Nothing worked so I learned to live with it. One day it magically fixed it self. Recently I rolled my computer back to a previous backup and I was having the problem again. CPU getting stuck at 0.78Ghz, computer barely usable for weeks. I tried the whole array of fixes but nothing worked either. Very frustrated, I cursed the computer in desperation and one hour later it was fine again. Magically fixed again. Hope this helps.

P.S. This useless story is actually for Dell. Dell, please investigate the issue and find out what actually fixes it so we don't waste our precious time. Cheers!

Thank you! I sloved the issue by your method, by opening the bottom panel and disconneting the battery. twice a year it happens, and I am afraid the screws will wear down eventually! 

@samos1111​ I have had this problem a several times, and its almost always due to temporary overheating, where the processor throttles down to 0.78Ghz, but stay there even if you shut the XPS15 off and restart when its ice cold.

This fix is almost always to disconnect the battery, but a laptop is not really meant to be taken apart too many times, and it should NOT be necessary Dell!!!! 

This is what you do instead:

First download throttle stop and see if you can unlock it.

If it can, dont leave it like that, it throttles for a reason and you might burn the processor under long heavy loads if it remains free to do so.

Instead of disconnection the battery, empty it to zero, but you cant do that under Windows - unless you really want to mess with Windows and that not necessesary.

Instead let Windows drain the battery untill I shuts down by itself.

Now, there will still be too much charge on the battery to make it appear disconnected, so boot the XPS-15 with any bootable partition program, cloning software, etc. I allredy have Todo Backup Restore as a boot option, so I use that, but any bootable program on a USB will do. Points is, almost all of these programs dont bother with how much the battery is charged or if the power suply is connected or not. They will simply keep running untill there is no charge left on the battery. This effectively drains the battery to zero ans make it appear disconnected. Try to restart and you will nothing happens. For good measure keep the start button pressed down for 30 seconds and then let go. Connect the power suply, wait a few minutes and then restart the XPS15. This has worked for me 8 times on 3 different machines. Try this before you let someone persuade you to replace the motherboard. Now, replacing that will work, but not for the reason people think. Its correlation and causation, and its a neat trick in order to get money from the customer, but the only reason replacing the motherboard works, is because when you do that, you have to disconnedt the battery - and that works.  

For a few days now I have had a very big problem with my laptop which is already under extended warranty (I don't remember 3-4 years).

The laptop operated at a speed of 0.78 GHz and the CPU utilization was a maximum of 28% - conditions in which it is impossible to work. The situation I am writing about happened after I had a damaged charging port and I contacted Dell Support to send me a service technician to repair the computer, but to my surprise they refused to do such a repair and only recommended doing the ePSA diagnostic test, after which the computer started working with with such low parameters as 0.78 GHz / 28%.

I had the problem for a few days until I managed to reach this forum and I confirm that I opened the laptop, disconnected the battery for about 5 minutes and that was enough for a complete repair.

However, Dell service recommended that I reinstall the system and sent me an English user manual for the laptop, which is a real joke.

Od kilku dni miałem bardzo duży problem z laptopem który jest już po przedłużanej gwarancji (nie pamiętam 3-4 lata).

Laptop działał z szybkością 0,78 GHz i wykorzystanie procesora było maksymalnie 28% - warunki w których nie da się pracować. Sytuacja o której piszę wydarzyła mi się po tym jak miałem uszkodzone gniazdo ładowania i skontaktowałem się z Support Dell aby wysłali mi serwisanta który dokona naprawy komputera, ale ku mojemu zdziwieniu odmówili takiej naprawy a zalecili jedynie zrobienie testu diagnostycznego ePSA właśnie po którym komputer zaczął pracować z tak niskimi parametrami 0,78 GHz / 28%.

Problem miałem przez kilka dni aż udało mi się dotrzeć na to forum i potwierdzam że rozkręciłem laptopa, odpiąłem baterię na ok 5 min i to wystarczyło do pełnej naprawy.

Natomiast serwis Dell zalecił mi re-instalację systemu i wysłał mi instrukcję obsługi w języku angielskim do laptopa, istna kpina.