Extreme power limit throttling on Spectre x360 Vega

[samu178564]

@AshGaunt: Are you sure you only have TPD limiting when in Tablet mode?

What happens when you stres your CPU for about 20min in normal laptop mode? Because on my PC there is no difference if its in Laptop or Tablet mode. Both are throtteling the same way down to - right now - 14/15W @ 2.2Ghz (I'm undervolted) @ 52°C in normal Laptop mode

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I still have the same question as in the beginning of this thread. Why throttling to 15W when I'm only at 52°C? Or is there something else on the Motherboard which demands the CPU to slow down like the Voltage regulators (like on the old XPS 15)??

[AshGaunt]

Yes I’m very sure. In tablet mode It starts off at full tdp for about 5 seconds then it shows only power throttling down to a core power of about 15watts. In pc mode it sometimes did that too and I only discovered this problem because it got stuck at 798mhz once (the result of full cpu use and 15watts I think). After a bios reinstall this went away but still it would throttle to less than 25 Watts after about 30 seconds of full cpu. What would happen that time in pc mode after the bios was it would go at full tdp when under full load and the temp would rise very quickly to about 90 degs, thermal throttling would come in which knocked the cpu back about 500mhz it seemed to 3.6ghz. The current throttle would come on and off too. It seemed stable but then after the 20-30 seconds (sometimes less if already hot) the power throttle would come on and stay on) temps would drop but it stayed on at about 29watts total package. Which at full cpu load was about 2.2ghz.

Then I used xtu to raise the power throttle level to 56.25watts. No higher than it can go anyway. I set this as a profile which loads at login. I also changed the priority of the windows power profile for less power saving. I made a sort of performance profile which still allowed processor parking and speed stepping but reacted faster and most importantly kept the ghz up when needed. After that all three indicators for throttling go on and off every few seconds but stays at about 3.6ghz without letting off.

As soon as I tilt the lid back, the keyboard icon pops onto the taskbar as you would expect and simultaneously the power throttle indicator comes on all the time and drops to 15watts. Even if it’s cold.

[samu178564]

I just got the problem with the CPU keeping stuck at 0.8Ghz / Power Limit Throttling again.

A reboot solved it for now, but the Vega GPU is still throttling to 400Mhz and not above that.

There seems to be really a problem with the drivers / BIOS somewhere

[naleman]

Had this problem and tried everything but eventually gave in after a week of experimenting and testing. Getting a refund and repurchasing the Spectre x360 Vega, will update on if the new device power limit throttles when I recieve it in within the next couple of weeks

[samu178564]

Since three days now the throttling problem is back!

After about 30min of usage the PC throttles down to 0.8Ghz until I reboot the whole machine. Then its ok again for 30min and then it starts again until .....

[naleman]

Update: New replacement device still power limit throttles, possibly even more than the last, so it's definitely a result of the inbuilt power settings that HP sets, sad that there is very little you can change in the BIOS to counteract the issue.

[AshGaunt]

Yes the problem is not solved, sometimes its fine, sometimes it throttles to 15W, it always throttles when in tent mode.

Its hidden in the bios, I cant find how to unhide the options, but if you load the bios file into AMIBCP, you can see all the options are in there, just hidden. I don't really have the knowledge (or balls) to risk a voided warranty and bricked laptop by trying to flash a modified one in...

I'm very sure that nobody from HP would want to help us though, even though it would take an HP bios engineer just a few minutes to change the limits.

Up until then though we shall have to maybe look at other ways to reslove the fact that they have ileagaly mis-sold a product with false statements on performance.

[curry684]

For vague reasons HP created a new thread from my reply: https://h30434.www3.hp.com/t5/Notebook-Hardware-and-Upgrade-Questions/Extreme-power-limit-throttling...

Did you ever get to fixing anything?

[samu178564]

I found a solution or an idea for a solution.

Overriding the Power Limit by Setting it back to for example 35W in XTU when it has changed.

The Problem is, that each time, the BIOS changes the TPD, you need to reset it in XTU, until the BIOS reaches the lowest TPD possible, where you set again 35W and the PC will keep this.

For me, while rendering a video, 35W is a good mark, where it will run at around 85°C with full vents. (Otherwise the BIOS will decrease the TPD so low, that the vents slow down)

XTU can also be called from Console. Perhaps someone has some time and wants to make a small batch script, running in Background and opening XTU with "set TPD to 35W" in Console every 30sec or as soon as the max allowed TPD goes below 35W.

[AshGaunt]

This is interesting.. I have sort of done this but not like that, maybe it can work. I have set up with a script on boot to load my XTU template, this does activate it. However I have not tried to run the script when it is trying to throttle it. From what you are saying this would keep it running fast. I will try it manually ans see if it works. If it does then I can send you my script and you can schedule it. Maybe can schedule the script to run in a more clever way if the TDP can be monitored by something which a script can monitor?