Extreme power limit throttling on Spectre x360 Vega

[bsmith9]

I've also had the problem of getting stuck at 800mhz.  If I leave it in that state long enough, it will eventually come out of it. I can also get it to come out of that state by briefly unplugging the power adapter, then plugging it back in.  When I've noticed it go into that state, temps have not been too bad, around 70C or so.

I've not had much issue with power throttling, although I have seen it.  I've got the laptop on a cooling stand which seems to help quite a bit.  Throttling is also much less with a .120v undervolt applied.  With no undervolt, it hits thermal throttling very quickly, then eventually hits power limit throttling too.  With the undervolt in place, it still will hit power limit throttling, but takes a while to get there.  This was tested using prime 95.

[Pilot7]

Guys I may have a solution for you.

go here:

 https://support.hp.com/us-en/drivers/selfservice/hp-spectre-15-ch000-x360-convertible-pc/16779588/mo...

and under drivers-chipset, download the intel dptf (windows 10 v1803) 8.3.10208.5644 

The other version is the one the laptop ships with from the factory and although it has a higher version number, it has an older date (go figure).

 This version allows the gpu to reach its full frequency (1011mhz instead of 985mhz), also the gpu doesn't get stuck at 400mhz like with the other one, and finally the laptop won't throttle based on the position of the lid (so full speed tent mode 😊).

 The only downside is that the cpu is temp limited to 85c (you may be able to work around that by rolling the three intel dptf generic participant drivers back to the original version).

As for the random bd prochot, I replied to a different thread, but I believe it is the power adapter overheating:

https://h30434.www3.hp.com/t5/Notebook-Hardware-and-Upgrade-Questions/HP-Spectre-x360-i7-8705G-runni...

I hope this does the trick for you

[bsmith9]

Thanks for your suggestion.  I checked and I had the older thermal framework driver installed & updated to the current one about a week ago.  Since then I've not yet seen the CPU stuck at 800mhz.

[bsmith9]

Looks like I commented too soon.  The same thing happened again today - with the chip stuck at 800mhz.  This happened within 15 minutes of booting .  I checked to ensure that the Windows v1803 driver was still installed.

[Pilot7]

Getting stuck at 800mhz from my experience is the power brick overheating and sending a bd-prochot signal until it cools down.

I ran multiple tests with the power brick on and off a cooling pad and the results were consistent.

The only solution that I’ve found is to make sure the battery is fully charged before a very demanding task, and hanging the power brick from its cord rather than letting it lay on its side, for better cooling.

Also keep in mind that if you’re reproducing the problem during a stress test, these types of loads are not very realistic. They tend to push the cpu and gpu in ways that normal programs won’t.

The drivers that I mentioned in my previous post solve the problem of the gpu never running at full speed and eventually getting stuck at 400mhz, but it’s completely independent from this problem.

[samu178564]

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@Pilot7 wrote:

Getting stuck at 800mhz from my experience is the power brick overheating and sending a bd-prochot signal until it cools down.

I ran multiple tests with the power brick on and off a cooling pad and the results were consistent.

The only solution that I’ve found is to make sure the battery is fully charged before a very demanding task, and hanging the power brick from its cord rather than letting it lay on its side, for better cooling.

Also keep in mind that if you’re reproducing the problem during a stress test, these types of loads are not very realistic. They tend to push the cpu and gpu in ways that normal programs won’t.

The drivers that I mentioned in my previous post solve the problem of the gpu never running at full speed and eventually getting stuck at 400mhz, but it’s completely independent from this problem.

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I'm not sure if it's the power brick. 

I tested the "new old" driver from above and I got the 800Mhz problem again, during some web brosing and movie watching - without the charger connected!

[yiorgos_n]

Solution: Just download and install ThrottleStop first to see what is actually going on with your machine and then to change your settings in a simple GUI interface:

https://www.notebookcheck.net/ThrottleStop-Primer.213140.0.html

Before downloading this I had to unplug the laptop and run it off the battery for a few minutes to clear the BiDirectional Processor Hot protection. otherwise known as BD PROCHOT protection.  Unplugging worked but temporarily.  ThrottleStop lets you tweak your settings and never throttle down.  Read the tutorial for more insight.  You do not have to be a gmae to appreciate what this does.  

[Pilot7]

I can attest it wasn’t the power brick after all.

I’m also using ThrottleStop to disable the BDprochot signal and stop the random throttling, but I don’t like this as a permanent solution.

I’ve opened a case with HP support and I was told that their engineering team is looking into it.

I doubt it’s a hardware problem, as all the units seem to exhibit it. It’s probably a bug somewhere.

[yiorgos_n]

I also agree it is not a hardware problem.  Once I fired up ThrottleStop, checked off SpeedStep, C1E adn BD PROCHOT and disabled Turbo it kept the temperature in the 70-80 degrees celsius range with all 8 threads working at 90%-100% at 3.1-3.4Ghz.  The output of my study trickles out results every 30-40seconds over days to weeks so keeping it humming was important for me without overheating or down throttling to 800Mhz. I am not using any graphics though.  I still think even if I was gaming, the machine can use some fine tuning by undervolting.  Before ThrottleStop the machine would Turbo boost for a few minutes with great results and then throttle down to 800Mhz and turning into a brick there for hours, making it unusable.

[Gretal]

I've found some information about this issue.

First, I've found the CPU only throttles to 800MHz sometimes after I turn off the Vega GPU. I'm not sure about the exact cause, but this is the only time this has happened to me.

Second, I've found that unplugging my laptop from it's charger after this happens makes the clock speeds go to normal again. You can plug it back in after this point, and clock speeds will still be normal.

Weird issue. Hope it gets fixed soon.